Earlier this week, Foreign Policy’s David Rothkopf reported that a source “close to White House discussions” believed that U.S. and Israeli planners were approaching agreement on the outlines of a joint, “surgical” strike on Iran’s nuclear program that would take place before U.S. elections next month.

This report is wildly improbable politically: on the same day it appeared, Prime Minister Netanyahu dissolved his government and called new elections, which will take place in January or February.

Perhaps more important, it is operationally improbable: senior Pentagon officials, Israeli experts, and outside military analysts have said again and again that there is no “surgical” strike option. Supporters and opponents have agreed that any strike, in order to have even a delaying effect on the Iranian nuclear program, would have to be sustained, broad, and massive.

Why? Let’s review.

Iran’s nuclear facilities are dispersed and hardened.

The two “surgical” strikes Israel has conducted on its neighbors’ nuclear facilities—Osirak in 1981 and Syria in 2007—were each focused on a single target. CSIS’s Anthony Cordesman has identified five nuclear facilities that U.S. planners would want to target in Iran. In addition, some of these have been hardened to deter just such attacks. Earlier this year, Secretary of Defense Leon Panetta told the Wall Street Journal that the United States did not currently have heavy-enough weaponry—a super bunker-buster—to destroy Iran’s most-hardened facilities. Israeli jets cannot carry the heaviest bombs the U.S. deploys; raids using those bombs require bigger jets, more escorts, more refueling.

American war planners, war games conducted by several research institutions, and independent analysts such as Cordesman and the recent “Iran Project” assessment of more than 30 retired Cabinet members, flag officers, and intelligence analysts—all of them have assumed that some targets would not be fully destroyed in a single wave, and that this outcome would be unacceptable to U.S. or Israeli leadership. The ability to send multiple waves after an initial attack requires the destruction of the enemy’s key military assets that could be used to strike back—not just radar and air defense systems but airfields, command and control facilities, and perhaps even the ballistic missile defense forces Iran has threatened to use in retaliation.

Rothkopf’s source seemed to acknowledge this, saying the operation could take anywhere from “a couple of hours” to “a day or two.” At some point, however, an operation that targets Iran’s whole nuclear infrastructure, air force, and command and control resembles a battlefield amputation, not modern surgery.

The trip to Iran and back is not a local flight.

In the case of Israel’s 2007 strike against Syria, a handful of fighter aircraft—perhaps as few as four—were able to fly across borders and reach their targets in minutes, with only a single air defense site to disable. In the Osirak attack, Israel’s airforce loaded 14 fighters to the brim with extra fuel to avoid having to refuel in the air; they avoided the worst of Iraq air defenses due in part, apparently, to negligence on the part of the Iraqis. In both cases, the air defenses Israel faced were relatively unsophisticated. Iran’s nuclear facilities are dispersed around the country, many hundreds of miles away from friendly bases or sea lanes from which jets could take off. Unless an attack is to be a suicide mission, planes—especially those taking off from Israel—must be able to refuel aerially during and after the mission, and that requires a squadron of tankers and support for them.

A responsibly executed attack takes time.

The NATO operation to knock out Libya’s air defenses took three days by itself. Iran’s air defenses and air force are considerably more sophisticated, not to mention more motivated, than their Libyan counterparts. As in Libya, though, some of the facilities will certainly be located in cities and residential areas. An outside attacker would likely choose to use extra precision munitions to minimize civilian casualties and political fallout—while remaining under no illusions that casualties could be avoided altogether. Advance warning of an attack on IAEA-inspected facilities would also have to be given in order to allow international personnel time to flee—further diminishing the “surgical” aspect of such a strike.

This is why Cordesman estimates that a mission that would set back Iran’s program as much as 10 years would require using many dozens—perhaps more—lanes, missiles, and drones over a period of days or longer.

No report, from public or private sources, has contradicted that assessment. Why would a smart and reputable writer report that decision-makers were giving serious consideration to an operational plan that in the past they have asserted would not work? It is possible that someone in the Israeli or U.S. government believes that renewing the Iranian government’s sense of imminent threat will help return it to the negotiating table. It is possible that someone in one or both governments believes that a “surgical” strike, even if it didn’t achieve the stated goal of significantly slowing the Iranian nuclear program, would lead Iran to negotiate seriously. Or it is possible that someone is using the reporter to try to change views in one or both governments about what next steps are advisable. That, too, is an operation. Call it brain surgery.