RED LIGHT, GREEN LIGHT: BIDEN HIS TIME ON IRAN.

Wordplay! But seriously: What to make of Vice President Joe Biden's comments this Sunday about a hypothetical Israeli strike on Iran's nuclear program? They have quickly become something of a Rorschach test where pundits go to see their worst fears confirmed -- Mark Lynch worries that Biden may have accidentally given the Israelis a "green light" -- or their hopes confirmed -- Rob and Matt believe this is an effort to distance the administration from anything that the Israelis might do. I'd observe that this definitely wasn't a gaffe -- look at how carefully Biden repeated his lines -- and that it seemed like interviewer George Stephanopolous was asking him what military steps the U.S. might take against Israel, which is sort of a strange question.

STEPHANOPOULOS: But just to be clear here, if the Israelis decide Iran is an existential threat, they have to take out the nuclear program, militarily the United States will not stand in the way?

BIDEN: Look, we cannot dictate to another sovereign nation what they can and cannot do when they make a determination, if they make a determination that they're existentially threatened and their survival is threatened by another country.

STEPHANOPOULOS: You say we can't dictate, but we can, if we choose to, deny over-flight rights here in Iraq. We can stand in the way of a military strike.

BIDEN: I'm not going to speculate, George, on those issues, other than to say Israel has a right to determine what's in its interests, and we have a right and we will determine what's in our interests.

That last comment seems to indicate that Biden doesn't see an Israeli strike as being in U.S. interests, or in Israel's either. My speculative assessment is that this could be an attempt to offer a clear choice to the Iranian regime, but more likely Biden was repeating standard diplomatic boilerplate that, in the current context, is given more value than it might otherwise deserve. (Incidentally, I had been prepared to remind everyone of how then-Secretary of State Dean Acheson started the Korean War with a speech that indicated that the U.S. wouldn't take action in the event of an invasion of North Korea by South Korea, but according to wikipedia Acheson's words actually didn't have a major effect.)

As we talk about "getting tougher" on Iran in response to the regime's decision to crush domestic opposition, and the impending reality that engagement may no longer be as practicable or effective as its proponents hope, it's important to remember that air strikes from Israel (or anywhere else) are not going to be very effective either. This paper looks at the potential for a strike, and concludes that it would likely accelerate nuclear development. Most important, perhaps, is this observation: "Limited intelligence about Iran’s nuclear programme means that many hundreds of strikes would still not destroy all nuclear related facilities and materials."

Ultimately, it's not clear that the U.S. and the rest of the international community have the capability to prevent Iran from acquiring nuclear weapons, should they want them, and if that capability exists, it's not clear whether we have the political will to pay the significant costs necessary to eliminate a nuclear program. The goal of U.S. strategy should be convincing Iran that they do not need a nuclear weapon to achieve their national interests. Part of that convincing is raising the costs of acquiring those weapons as high as we feasibly can, but the other part is taking whatever actions will show Iran that a massively destructive weapon isn't key to being a successful state. Bombing them will not achieve that aim, and, as others have pointed out, there is the problem that those bombs could end up falling on the many Iranians we have recently found to be fellow travelers on the road to democracy.

-- Tim Fernholz