In the city of Bandar Abbas, an Iranian vendor fills gasoline for a customer. (AP Photo)

The great Iran policy debate landed this week back on the longstanding notion that the international community might ban gasoline exports to Iran. Legislation along these lines is being pushed by the American Israel Public Affairs Committee (AIPAC) on the Hill, and David Sanger reported in Monday's New York Times that the administration is discussing the potential sanction with congressional leaders, Israel, and European allies. This, hawks hope, will provide enough coercion to make Iran do what they want without the need for military aggression.

Why this particular notion has such a grip on the minds of hawks isn't totally clear to me, but I suppose the idea is that there's something amusingly ironic about using gasoline as a weapon against a major oil exporter. Iran, you see, is rich in oil but poor in oil refineries and consequently imports the majority of its refined petroleum products, including gasoline. Prevent the export of gasoline to Iran and prices will rise, likely forcing the government to implement a rationing scheme.

Irony aside, this seems like a poor choice of sanction. Iran relies on imports for most of its gasoline, but not all of it. If shortages arise, the regime will presumably allocate an adequate quantity to the security services and elite officials, while pushing the brunt of the suffering onto the broad mass of people. Sanctions have helped impoverish Cuba, but the Castros enjoy a perfectly decent standard of living. A gasoline-deprived Iran would create a similar situation. Ordinary Iranians would suffer, but the leadership probably would not. It's possible, I suppose, that Iranians would react to gas lines with a renewed protest movement that somehow (magic?) would become more immune to Basiji bullets than proved to be the case in the wake of Iran's presidential election. On the other hand, Iran's leaders could plausibly bolster their recently damaged legitimacy by arguing that the West was attempting to cripple the Iranian economy even though the Iranians aren't doing anything that Israel, Pakistan, India, France, Britain, China, Russia, and the United States haven't already done by developing nuclear weapons.

The ensuing crisis would provide not just the pretext for a renewed crackdown on Iranian dissidents but a new means with which to punish undesirable figures. Those seen at opposition rallies or the like might find their ration tickets missing, for example.

But the merits of the proposal aside, the scheme's crippling flaw is that the United States simply lacks the ability to make it happen. You would need Russia and China, among others, to actively participate in implementing and enforcing the embargo for it to have any success. As Daniel Drezner, author of The Sanctions Paradox and someone who thinks a gasoline embargo is "absolutely" a good idea, put it, "If you read any story about a gasoline embargo on Iran, just scan quickly and get to the part where the reporter explains how and why Russia and China would go along. If it's not mentioned, the story is inconsequential."

But what goes for reporters goes doubly for politicians and lobbyists. Many members of Congress have already signed on to a gas embargo, and more are being actively recruited. And here the question is not so much why Russia and China would go along with this scheme, but what are policy-makers prepared to do to persuade them to do so? As a major oil exporter, Russia, really, is the key actor here. And there are plenty of issues on the U.S.-Russian bilateral agenda that could, in theory, be traded off in exchange for Russia joining an embargo. But the voices calling loudest for tough action against Iran tend to be the same ones asking us to construct an anti-Russian ballistic missile shield. They're also the ones who last year shouted about the world-historical importance of defending Georgia against Russian aggression. Indeed, they freak out at even modest and mutually beneficial U.S.-Russian agreements to reduce stockpiles of nuclear weapons.

The reality is that nobody wants to make a gasoline sanction against Iran the top item on the agenda with Moscow. Which is fine. But if that's the case, then we ought to stop deluding ourselves that there's some magical embargo scheme capable of bringing the Iranian regime to heel. What's been true for years continues to be true -- there are no good alternatives to a policy of engagement, aimed at brokering a deal in which Iran verifiably foreswears nuclear weapons in exchange for a better relationship with the United States.

It's worth recalling that Iran is already sanctioned quite heavily in ways that do concrete harm. Indeed, sanctions preventing the export of necessary capital and technology are one of the reasons Iran's oil-refining capabilities are so limited in the first place. The reasonable thing for the Iranians to do would be to strike a deal with us, just as they attempted to do back in 2002 and 2003. And it would have been smart for us to say "yes" at the time, and it's still in our interest to try to resolve the nuclear issue with Iran today. Recent events in Iran naturally make one skeptical that the Iranians are interested in being reasonable. And if it's not possible to strike a deal, then trying to nudge the international community toward a policy of containment and additional sanctions will be the best we can do.

If that's what it comes to, so be it. But we shouldn't kid ourselves that such a policy is likely to work. Engagement remains overwhelmingly the best answer, and wishful thinking about a gasoline embargo smacks of an effort to distract from that reality.