WarSclerotic

Strait of Hormuz shutdown: Iran could close passageway — and destroy itself in the process | News | National Post.

Reuters  Jan 5, 2012 – 7:56 AM ET | Last Updated: Jan 5, 2012 8:01 AM ET

EBRAHIM NOROOZI/AFP/Getty Images

Iranian military personnel place a national flag on a submarine during the “Velayat-90” navy exercises in the Strait of Hormuz in southern Iran on January 3, 2012, the End day of ten-day war games. Iran’s military warned one of the US navy’s biggest aircraft carriers to keep away from the Gulf, in an escalating showdown over Tehran’s nuclear drive that could pitch into armed confrontation.

By Peter Apps
Reuters Political Risk Correspondent

LONDON — Should Iran’s rulers ever make good their threats to block the Strait of Hormuz, they could almost certainly achieve their aim within a matter of hours.

But they could also find themselves sparking a punishing — if perhaps short-lived — regional conflict from which they could emerge the primary losers.

In recent weeks, a growing number of senior Iranian military and civilian officials have warned that Tehran could use force to close the 54 km entrance to the Gulf if Western states impose sanctions that paralyze their oil exports.

In 10 days of highly publicized military exercises, state television showed truck-mounted missiles blasting towards international waters, fast gunboats practicing attacks and helicopters deploying divers and naval commandos.

Few believe Tehran could keep the straits closed for long — perhaps no more than a handful of days — but that alone would still temporarily block shipment of a fifth of all traded global oil, sending prices rocketing and severely denting hopes of global economic recovery.

But such action would swiftly trigger retaliation from the United States and others that could leave the Islamic republic militarily and economically crippled.

“They can cause a great deal of mischief… but it depends how much pain they are willing to accept,” says Nikolas Gvosdev, professor of national security studies at the U.S. Naval War College in Rhode Island.

He said he believed Tehran would only take such action as a last resort: “They are much more likely to threaten than to act.”

The true purpose of its recent sabre-rattling, many analysts suspect, may be more a mixture of deterring foreign powers from new sanctions and distracting voters from rising domestic woes ahead of legislative elections in March.

With the United States signing new sanctions into law on New Year’s Eve — although they will not enter force until the middle of the year — and the European Union considering similar steps, few expect the pressure on Tehran to let up.

“This is probably less a genuine military threat than a bid to put economic pressure back on the West and split Western powers over sanctions that threaten Iran’s oil economy,” says Henry Wilkinson, head of intelligence and analysis at London security consultants Janusian.

“Iran now does not have much to lose by making such a threat and a lot to gain.”

National Post Graphics

Click to enlarge this map of the region

But many fear the more Iran is pushed into a corner, the greater the risk of miscalculation.

Its ruling establishment is also widely seen as deeply divided, with some elements — particularly the well-equipped and hardline Revolutionary Guard — much keener on confrontation than others.

SEA MINES, MISSILES, SUBMARINES, SPEEDBOATS

“I cannot see strategic sense in closing the straits, but then I do not understand the Iranian version of the ‘rational actor’,” said one senior Western naval officer on condition of anonymity.

“[But] one can be pretty certain that they will misjudge the Western reaction… They clearly find us as hard to read as we find them.”

The capability to wreak at least temporary chaos, however, is unquestionably there.

The U.S. Fifth Fleet always keeps one or two aircraft carrier battle groups either in the Gulf or within striking distance in the Indian Ocean.

Keenly aware of conventional U.S. military dominance in the region, Iran has adopted what strategists describe as an “asymmetric” approach.

Missiles mounted on civilian trucks can be concealed around the coastline, tiny civilian dhows and fishing vessels can be used to lay mines, and midget submarines can be hidden in the shallows to launch more sophisticated “smart mines” and homing torpedoes.

Iran is also believed to have built up fleets of perhaps hundreds of small fast attack craft including tiny suicide speedboats, learning from the example of Sri Lanka’s Tamil Tiger rebels who used such methods in a war with the government.

At worst, its forces could strike simultaneously at multiple ships passing out of the Gulf, leaving a string of burning tankers and perhaps also Western warships.

But a more likely initial scenario, many experts believe, is that it would simply declare a blockade, perhaps fire warning shots at ships and announce it had laid a minefield.

“All the Iranians have to do is say they mined the straight and all tanker traffic would cease immediately,” says Jon Rosamund, head of the maritime desk at specialist publishers and consultancy IHS Jane’s.

RETALIATION, ESCALATION

U.S. and other military forces would find themselves swiftly pushed by shippers and consumers to force a route through with minesweepers and other warships — effectively daring Tehran to fire or be revealed to have made an empty threat.

During the so-called “tanker war” of the mid-1980s, Gulf waters were periodically mined as Iran and Iraq attacked each other’s oil shipments.

U.S., British and other foreign forces responded by escorting other nations’ tankers — as well as conducting limited strikes on Iranian maritime targets.

This time, retaliation could go much further. In closing the straits, Tehran would have committed an act of war and that might prove simply too tempting an opportunity for its foes to pass up.

“We might well take the opportunity to take out their entire defense system,” said veteran former U.S. intelligence official Anthony Cortesman, now Burke Chair of Strategy at the Centre for Strategic and International Studies in Washington DC.

“You’d almost certainly also see serious strikes on their nuclear facilities. Once the Iranians have initiated hostilities, there is no set level at which you have to stop escalation.”

Whilst in theory it would be possible to push heavily protected convoys through the straits even in the face of Iranian attack, few believe shippers or insurers would have the appetite for the level of casualties that could involve.

Instead, they would probably hold back until Tehran’s military had been sufficiently degraded. That, Western military officers confidently say, would only be a matter of time.

“Anti-ship cruise missiles are mobile, yet can… be found and destroyed,” said one U.S. naval officer with considerable experience in the region, speaking on condition of anonymity.

“Submarines are short-duration threats — they eventually have to come to port for resupply and when they do they will be sitting ducks.”

“DANGEROUS GAME OF CHICKEN”

Given the forces arrayed against them, many analysts believe Tehran will ultimately keep the straits open — not least to allow their own oil exports to flow — whilst finding other ways to needle its foes.

If they did wish to disrupt shipping, they could briefly close off areas of the Gulf through declaring “military exercise areas,” “accidentally” release oil into the main channel or perhaps launch one-off and more deniable hit-and-run attacks.

The rhetoric, however, looks almost certain to continue.

“This isn’t the first time we have heard these types of threats,” said Alan Fraser, Middle East analyst for London-based risk consultancy AKE. “Closing of the Straits of Hormuz is the perfect issue to talk about because the stakes are potentially so high that nobody wants it to happen.”

Henry Smith, Middle East analyst at consultancy Control Risks, says he believes the only circumstances under which the Iranians would consider such action would be if the United States or Israel had already launched an overt military strike on nuclear facilities.

“Then, I think it would happen pretty much automatically,” he said. “The Iranians have been saying for a long time that is an option, and they would have little choice but to stick to that. But otherwise, I think it’s very unlikely.”

For many long-term watchers of the region, the real risk remains that in playing largely to domestic audiences, policymakers in Washington, Tel Aviv and Tehran inadvertently spark something much worse than they ever intended.

“Both sides are talking tough,” said Farhang Jahanpour, associate fellow at the Faculty of Oriental Studies at Oxford University. “Unfortunately it can very easily get out of hand and cause a conflagration. I blame hardliners on both sides. They are playing a very dangerous game of chicken.”

With files from William Maclean

How Serious Are Iran’s Threats? – Council on Foreign Relations.

January 5, 2012

UK warns Iran: Close Hormuz at your own … JPost – International.

    The UK may take military action against Iran if it carries out its threat to block the Strait of Hormuz, Defense Secretary Philip Hammond will warn in a speech in Washington today.

Any attempt by Iran to block the strategically important waterway in retaliation for sanctions against its oil exports would be “illegal and unsuccessful” and the Royal Navy will join any action to keep it open, Hammond will say, according to extracts of the address released by his office.

“Our joint naval presence in the Arabian Gulf, something our regional partners appreciate, is key to keeping the Straits of Hormuz open for international trade,” Hammond will say. “Disruption to the flow of oil through the Straits of Hormuz would threaten regional and global economic growth,” he will say, arguing that “it is in all our interests that the arteries of global trade are kept free, open and running.”

Iran will block the strait if sanctions are imposed on its crude-oil exports in an attempt to force the Islamic republic to abandon its nuclear program, Vice President Mohammad Reza Rahimi said on Dec. 27. Britain and France will press for the EU to impose an embargo on Iranian oil imports when foreign ministers meet in Brussels on Jan. 30.

About 15.5 million barrels of oil a day, or a sixth of global consumption, flows through the Strait of Hormuz, between Iran and Oman at the mouth of the Persian Gulf, according to the US Department of Energy. The Royal Navy will continue to play a “substantial” role in the combined maritime force to help maintain freedom of navigation, Hammond will say.

Hammond, who will meet with US Defense Secretary Leon Panetta on Thursday, will also use the speech, at the Atlantic Council, to criticize other members of the North Atlantic Treaty Organization for not being willing to commit resources to joint operations, including in Libya and Afghanistan, his office said.

“Too many countries are failing to meet their financial responsibilities to NATO, and so failing to maintain appropriate and proportionate capabilities,” Hammond will say. “Too many are opting out of operations or contributing but a fraction of what they should be capable of. This is a European problem, not an American one. And it is a political problem, not a military one.”

Budget cuts mean that many nations are having to trim defense spending and they need to find “smarter ways of working together to get greater capability from the resources that exist,” Hammond will say.

“Without strong economies and stable public finances it is impossible to build and sustain, in the long term, the military capability required to project power and maintain defense,” Hammond will say. “That is why today the debt crisis should be considered the greatest strategic threat to the future security of our nations.”

‘Attacks on Iran won’t be allowed from Tur… JPost – Middle East.

    Turkish Foreign Minister Ahmet Davutoglu vowed Thursday that his country would not allow attacks on Iran to be carried out from its territory, Turkish daily Hurriyet reported.

Davutoglu made the comments at a joint press conference in Tehran with his Iranian counterpart Ali Akbar Salehi.
The Turkish foreign minister attempted to dispel rumors that the NATO missile shield recently stationed in Turkey, should pose as a threat to Iran or damage relations between the countries.

Davutoglu stated that Turkey and Iran trust each other. “I certainly do not see Iran as a threat,” Hurriyet quoted Davutoglu as saying.

The Turkish foreign minister arrived in Iran on Wednesday for talks with Salehi on Iran’s nuclear program and developments in neighboring Iraq and Syria.

Davutoglu’s visit was described as being in the framework of regular talks between the two ministers, but it comes at a key time for the region and relations between the two regional powers.

“It is intended that they will exchange views on topical subjects such as Iran’s nuclear program and developments in Syria and Iraq,” the Turkish foreign ministry said.

Davutoglu’s visit was set to finish on Thursday.

Turkey is evaluating whether to seek a waiver from the United States to exempt Turkish oil importer Tupras from new US sanctions on institutions that deal with Iran’s central bank, a Turkish official said on Tuesday.

US ally Turkey is among the biggest buyers of Iranian oil and gas. It gets about 30 percent of its oil from neighbor Iran, and Tupras, Turkey’s biggest crude oil importer is a big buyer of Iranian crude.

Reuters contributed to this report.

The U.S. and Iran Are Already Locked in Economic War – Yochi J. Dreazen – International – The Atlantic.

By Yochi J. Dreazen

Bombs may not be falling, but sanctions and markets are the new, hard-hitting tools of this escalating conflict

Iranian Navy commander Habibollah Sayyari points while standing on a naval ship on the Sea of Oman near the Strait of Hormuz in southern Iran / Reuters

Hard-hitting U.S. sanctions on Iran’s central bank and new Iranian threats to attack U.S. vessels in a vital oil-shipping route underscore a little-noticed aspect of the growing tensions between Washington and Tehran: Armed conflict may not break out anytime soon, but Iran and the U.S. are already fighting a low-level economic war that seems likely to escalate in the months ahead.

Iran’s apparent progress toward building both nuclear weapons and the long-range missiles capable of carrying them to targets in both Israel and Europe has prompted mounting speculation that Washington or Jerusalem will soon carry out full-scale military strikes against Iran, attacks likely to trigger a major regional conflict.

For now, that talk seems overblown. But the economic sparring between the U.S. and Iran is continuing to intensify, a sign that the two countries have ways of fighting each other that don’t require the use of armed force. In the last month alone, Congress voted to directly target Iran’s oil sector by isolating the country’s central bank from the world financial system, and Iran threatened to close the Straits of Hormuz, the passageway for more than a fifth of the world’s oil.

Tensions between Washington and Tehran flared even higher on Tuesday, with Iran warning that it would take unspecified actions if a U.S. warship returned to the Straits of Hormuz. “I recommend and emphasize to the American carrier not to return,” said Ataollah Salehi, chief of staff of the Iranian Army. “We are not in the habit of warning more than once.”

The comments were widely interpreted in the region as a direct threat to the U.S., and the Pentagon said on Tuesday that the “deployment of U.S. military assets in the Persian Gulf region will continue as it has for decades.” The Straits of Hormuz are considered to be international waters, which means Iran has no legal basis for threatening to close them off.

Suzanne Maloney, an expert on the Iranian economy at the Brookings Institution, said the two countries are already looking for ways of hurting each other that stop short of full military conflict.

“It’s not an overstatement to say that the sanctions we’ve put on Iran in recent weeks constitute a full-fledged attack on the Iranian economy,” she said in an interview. “This is now a regime that sees itself locked with an existential conflict with the U.S., and they’re going to use every lever at their disposal–economic, irregular warfare, public diplomacy–to fight back.”

Oil is emerging as the first battleground between the two countries. World energy prices have been steadily rising because of Iran’s threats to close the Straits of Hormuz, and Tehran’s new warnings about attacking U.S. vessels there sent them spiraling still higher. By midday Tuesday, crude futures were up $4 a barrel, pushing prices above $111 a barrel, according to Reuters.

The U.S. and its allies, meanwhile, are ratcheting up their pressure on Iran’s oil sector, the most important part of the country’s overall economy. President Obama signed legislation on New Year’s Eve that blocks financial institutions that deal with Iran’s central bank from doing any business with American financial institutions, effectively isolating Iran economically. The European Union is expected to impose similar measures later this month.

U.S. economic sanctions are already hitting Iran hard. Iran’s currency, the rial, fell to a historic low against the dollar on Tuesday and is down nearly 40 percent since December. In an ironic twist, press reports from Iran said that businessmen, oil traders, and ordinary citizens were frantically trying to buy dollars out of fears the rial will soon slump even further.

Iran seems likely to respond to the new sanctions, though it’s not clear how or when. Speaking to a gathering of military officials in November, Ayatalloh Ali Khamenei, the country’s supreme leader, said “we respond to threats with threats.” With the two countries locked in a spiraling financial and political conflict, the economic war between the two countries will continue to rage–and intensify–into the foreseeable future.

Arabian Aerospace – INEGMA outlines scenario of an Iranian Preemptive Attack to Control Gulf Waters.

Riad Kahwaji, the CEO of INEGMA outlines the possibility of an Iranian preemptive attack to control Gulf waters

DEBKAfile, Political Analysis, Espionage, Terrorism, Security.

DEBKAfile Exclusive Report January 5, 2012, 10:35 AM (GMT+02:00)

Bombs in the hold of the USS Stennis

The armies of Saudi Arabia and fellow Gulf Cooperation Council states stood ready Thursday Jan. 5, for Washington to stand up to Iranian threats and send an aircraft carrier or several warships through the Strait of Hormuz into the Persian Gulf. Riyadh has been leaning hard on the Obama administration not to let Tehran get away with its warning to react with “full force” if the USS Stennis aircraft carrier tried to reenter the Gulf or Iran’s pretensions to control the traffic transiting the world’s most important oil route.

Wednesday night, the Iranian parliament began drafting a bill prohibiting foreign warships from entering the Gulf without Tehran’s permission.
debkafile‘s Washington sources report that Saudi Arabia has warned the Obama administration that Iranian leaders mean what they say; their leaders are bent on provoking a military clash with the United States at a time and place of their choosing, rather than leaving the initiative to Washington. To this end, Iranian officials are ratcheting up their belligerence day after day.
Notwithstanding their military inferiority, the Iranians believe they can snatch a measure of success from a military confrontation, just as the Lebanese Hizballah did in the 2006 war against Israel. In any case, they expect any clash to be limited – at least at first. The two sides will begin by feeling for the opposite side’s weaknesses while endeavoring to hold the line against a full-blown war.

America’s failure to rise to Iran’s challenge will confirm its rulers in the conviction that the US is a paper tiger and encourage them to press their advantage for new gains.
The assessment of British military experts Thursday, Jan. 5, was that the question now is: Who will blink first? Will the US follow through on the Pentagon’s assertion that the deployment of US military assets in the Persian Gulf will continue as it has for decades? Or will Iran act on its warnings and block those waters to the entry of American warships?
President Barack Obama can’t afford to cave in to Iran, especially while campaigning for reelection in Nov. 2012; Tehran, for its part, has made too many threats to easily back down.
The entire region is now on tenterhooks for the next move, with US, Iranian and Gulf armies on the highest war alert. American and Iranian war planners both accept that their advantage lies in surprising the enemy – without, however, catapulting the Persian Gulf into a full-dress war.
US Navy publications as of Wednesday, Jan. 4 showed a sign of the times:  One ran a series of photos of F-18 Super Hornet fighter-bombers standing on the runways of the USS Stennis aircraft carrier ready for takeoff at any moment. Another depicted for the first time ever row upon row of huge bombs in the carrier’s hold to show the Iranians what they are taking on.

In the view of debkafile’s military sources, the fact that the US has deployed only one large aircraft carrier in the region does not signify any reluctance on Washington’s part to preserve the freedom of navigation in the Strait of Hormuz and the Persian Gulf. There is no longer a need to rush more carriers to a flashpoint in these strategic waters. The US maintains five huge air bases in the Gulf region – two, the Ali Al Salem and Ahmed Al Jaber bases, in Kuwait;  the Al Dhafra base in the UAE; and the largest air bases outside the US – Al Adid in Qatar and the Thumrait in Oman.

The concentration of aircraft carriers at any given location is no longer treated as the marker of an imminent US military operation.

BREAKING NEWS: The Pentagon to Send US Troops to Israel. Iran is the Unspoken Target.

Global Research, January 4, 2012

January 2, 2012. Jerusalem. In one of the most blacked-out stories in America right now, the US military is preparing to send thousands of US troops, along with US Naval anti-missile ships and accompanying support personnel, to Israel.

It took forever to find a second source for confirmation of this story and both relatively mainstream media outlets are in Israel. With one source saying the military deployment and corresponding exercises are to occur in January, the source providing most of the details suggests it will occur later this spring. Calling it not just an “exercise”, but a “deployment”, the Jerusalem Post quotes US Lt.-Gen Frank Gorenc, Commander of the US Third Air Force based in Germany. The US Commander visited Israel two weeks ago to confirm details for “the deployment of several thousand American soldiers to Israel.” In an effort to respond to recent Iranian threats and counter-threats, Israel announced the largest ever missile defense exercise in its history. Now, it’s reported that the US military, including the US Navy, will be stationed throughout Israel, also taking part.

While American troops will be stationed in Israel for an unspecified amount of time, Israeli military personnel will be added to EUCOM in Germany. EUCOM stands for United States European Command.

In preparation for anticipated Iranian missile attacks upon Israel, the US is reportedly bringing its THAAD, Terminal High Altitude Area Defense, and ship-based Aegis ballistic missile systems to Israel. The US forces will join Israeli missile defense systems like the Patriot and Arrow. The deployment comes with “the ultimate goal of establishing joint task forces in the event of a large-scale conflict in the Middle East”.

The Jerusalem Post reports that US Lt.-Gen Frank Gorenc was in Israel meeting with his Israeli counterpart, Brig.-Gen Doron Gavish, commander of the Air Defense Division. While there, the US General visited one of Israel’s three ‘Iron Dome’ anti-missile outposts. The Israeli Air Force has announced plans to deploy a fourth Iron Dome system in the coming months. Additional spending increases in the Jewish state will guarantee the manufacture and deployment of three more Iron Dome systems by the end of 2012. The Israelis are hoping to eventually have at least a dozen of the anti-missile systems deployed along its northern and southern borders.

In a show of escalated tensions in the region, Iran test fired two long range missiles today. One, called the Qadar, is a powerful sea-to-shore missile. The other was an advanced surface-to-surface missile called the Nour. According to Iranian state news, the Nour is an ‘advanced radar-evading, target-seeking, guided and controlled missile’. Additionally, the Iranian military reportedly test-fired numerous other short, medium and long-range missiles. Yesterday, Iranian authorities reported that they test-fired the medium-range, surface-to-air, radar-evading Mehrab missile. Today is supposed to be the final day of Iranian naval drills in the Straits of Hormuz.

Iran recently made global headlines when it threatened to blockade the Straits of Hormuz if Europe and the US went ahead with their boycott of Iranian oil and the country’s central bank. One-quarter of the world’s oil passes through that waterway every day. President Obama has announced that a closure of the Straits was unacceptable and vowed to take whatever measures are necessary to keep the vital shipping lane open.

In response to the Iranian missile tests this weekend, French authorities were the first to respond, calling it a, “very bad signal to the international community.”We want to underline that the development by Iran of a missile program is a source of great concern to the international community,”the French Foreign Ministry said in a written statement. Israeli officials suggested the flamboyant Iranian military drills this weekend were a sign that international sanctions on the country were taking a heavy toll and that any additional boycotts, on its banks or oil industry, would be crippling.

Israeli Defense Minister Ehud Barak said the large missile tests showed, “the dire straits of Iran in light of the tightening sanctions around her, including the considerations in the last few days regarding the sanctions of exporting petroleum as well as the possibility of sanctions against the Iranian Central Bank.” While the chances of Iran going through with its threat of closing the Strait of Hormuz are slim, the deployment of thousands of US troops and naval ships to Israel shows the US isn’t taking any chances.

U.S.-Iran Tensions: Mideast Showdown Builds As United States Tightens Military Ties To Israel.

WASHINGTON — Storm clouds darkening over the Middle East suggest a growing peril for the United States and the possibility of a new war that could embroil the U.S., Israel, Iran and others in a bloody, costly fight.

Behind this week’s exchange of threats between Iran and the United States over access to the Persian Gulf, seasoned analysts see a perfect storm of factors that could trigger armed conflict.

Iran’s work on nuclear weapons is fast approaching a “red line,” the crossing of which both the United States and Israel say is unacceptable and may have to be halted by force. Washington and European capitals are preparing new sanctions that would sever Iran from the international banking system, a move that would cripple its economy and that Tehran has said it would consider a provocation to war. Growing violence in Syria threatens to spill over its borders with Israel, Lebanon and Turkey, a NATO ally.

Amid the saber-rattling rhetoric from Washington and Tehran, and Arab world upheaval from Egypt to Iraq to Yemen, the United States is planning an unprecedented escalation of military cooperation with Israel, including massive joint exercises this spring to practice joint command and maneuver of ground forces in combat.

And political campaigns, including a struggle between bitterly opposed factions in Iran’s March parliamentary elections and the U.S. presidential contest culminating in the fall, are likely to keep all these tensions at a boil.

“‘Powder keg’ doesn’t begin to describe it,” said Louise Arbour, president of the International Crisis Group, an independent organization that monitors global tensions. “Rising strategic stakes have heightened the regional and wider international competition,” she wrote in a new assessment. It is, she concluded, “an explosive mix.”

U.S. Defense Secretary Leon Panetta said last month that the planned maneuvers with Israel, dubbed Austere Challenge, will be “the largest joint exercise in the history” of U.S.-Israeli relations. What had been a biannual series of command-post computer training with simulated forces held in Germany has been expanded this year to Israel and will include U.S. Army combat troops on the ground in Israel, commanded and maneuvered by joint U.S.-Israeli command centers in Europe and Israel.

The joint maneuvers are part of what Panetta has called “unprecedented defense cooperation” with Israel, which also includes joint naval exercises and the training of U.S. Marines on counterterror and urban warfare operations with Israeli commandos.

Austere Challenge will play out in May, shortly after a massive joint missile defense exercise, Juniper Cobra, that will involve U.S. and Israeli defense systems and missile interceptors.

U.S. officials in Washington and Europe declined to provide details on the joint exercises. Air Force Capt. John Ross, a spokesman for the U.S. European Command, which will conduct Austere Challenge, said the exercise “is not in response to any real-world event.”

But Iran’s work on its nuclear weapons, newly documented last month by the inspectors of the International Atomic Energy Agency, is driving events at a fast clip. Panetta has said Iran could have a nuclear bomb in “about a year … perhaps a little less” if Iran, as suspected, has a secret uranium enriching facility.

Should Iran cross that “red line,” Panetta told CBS News on Dec. 19, “we will take whatever steps necessary to stop it.”

The Obama administration and others have tried economic sanctions to drive Iran to abandon its nuclear program. According to a recent report by the Congressional Research Service, the extensive web of international sanctions against Iran is not having an appreciable impact on its economy, which is growing at an enviable 3.5 percent annual rate. But Iran’s economy — and particularly its state-subsidized imports of food and gasoline — depends on unfettered access to global financial markets.

Legislation reluctantly signed into law by President Barack Obama last week requires the president within 180 days to impose sanctions on any foreign financial institutions that deal with Iran’s central bank. Widespread refusal to deal with Iran’s central bank would strangle the country’s access to hard currency from its oil revenues, which earn Iran, as the world’s fourth-largest oil exporter, about $75 billion a year.

In response, Iran has threatened to close the Persian Gulf at its chokepoint, the Strait of Hormuz, through which pass some two dozen giant oil tankers a day carrying one-third of the world’s oil consumption.

Although the president can waive the new sanctions for 120 days at a time, a White House spokesman said the administration is working with its European allies and others “to be in a position to most effectively implement” the sanctions, seeking to “avoid negative repercussions to international oil markets.”

In anticipation of an oil trade war — or worse — oil prices have risen sharply this week, and Iran’s currency, the rial, briefly fell to a new low in a signal of rising consumer prices for food and fuel.

The risk, of course, is that the heated rhetoric and implied threats gain a momentum of their own. “As these things go forward it’s more difficult to step back,” said Michael Adler, an Iran scholar at the Woodrow Wilson International Center in Washington. Speaking of the region as a whole, he added, “It’s a tinderbox squared or cubed.”

The unintended danger arising from the threatened sanctions is that they might push the U.S. and Iran toward conflict rather than toward a peaceful conclusion, warned Vali Nasr, a senior fellow at the Brookings Institution, a Washington think tank. “This is a significant escalation of tension between the United States and Iran, and the start of a more dangerous phase in the West’s attempt to curtail Iran’s nuclear program,” he wrote in a new analysis.

“War between the U.S. and Iran may very well start, not if and when Washington decides to strike against Iran’s nuclear facilities, but because sanctions designed as the alternative to military action end up hastening its advent,” Nasr wrote.