Engaging Iran ... Seymour Hersh is the New Yorker writer who broke the Abu Ghraib story. Last night Hersh went on the Daily Show and said he'd heard, among other things, that Iran was talking with Venezuela about causing an oil shock in order to pressure the U.S. to withdraw from Iraq.

That seems like a bit of a stretch to me -- or better, exactly the kind of ploy Iran wants to have floated around so it can use the mere threat of a shock to gain political leverage.

But however implausible that scenario is, the fact that a credible reporter can publicly air it speaks volumes about the leverage Iran already has. Whatever Iran wants to do domestically, we are utterly powerless to stop: our military is tied up elsewhere, and after twenty-five years of sanctions, Iran's economy is now impervious to them. The only avenue left -- to sanction individual companies that finance Iranian programs we don't like -- is also purposeless, because those "individual companies" are all Russian banks.

So Iran's domestic sovereignty is pretty much absolute. Which means it will get its nuclear weapons sometime soon, and, in turn, means its foreign policy will become increasingly powerful too. Compound this with a Shiite Iraq, and Iran suddenly emerges as the dominant force in the region.

The question is what the U.S. should be doing about it. And far from continuing our futile attempt at isolating the country, we should be engaging it. Reduce sanctions, generate foreign investment, and do what we can to foster an Iranian business community that is strong enough and influential enough to check the use of nuclear weapons once they develop them.

As Hersh is all too aware, a nuclear Iran and a regionally polar Iran are now givens. We need to have policies in place which recognize its growing stature and seek to influence its authority rather than isolate it.