SINCE Barack Obama's victory, the concept of "talking to Iran" has become Washington's flavor of the month.

Talking to Iran, of course, was one of candidate Obama's main foreign-policy planks. It sounded both intelligent and attractive. After all, if one could achieve all those desirable results just by talking to the mullahs, why not?

There's a hitch, however.

Obama appears to be having second thoughts about the wisdom of an idea announced largely as a means of strengthening his anti-Bush message rather than dealing with a dangerous foreign foe. All indications from him since his election are that he's in no hurry to open talks.

The other day, in response to a cable from President Mahmoud Ahmadinejad congratulating him on his win, Obama indicated he was in no mood to accept the Iranian's invitation to dance - for several reasons.

To start with, he has realized that his offer of unconditional talks with Tehran could destroy the six-nation coalition that has managed to pass three United Nations Security Council resolutions imposing sanctions on the Islamic Republic. Some allies, including France, have issued direct warnings that Obama's campaign promise may encourage Iran to speed up its nuclear program. Israel's Foreign Minister Tzipi Livni, for her part, has indicated "deep reservations" about Obama's Iran gambit.

More important, perhaps, with the election over, Obama remembers that talking to the mullahs is nothing new. First launched by West German Foreign Minister Hans-Dietrich Genscher in 1980, it has been tried by the European Union, successive US administrations and several Arab countries for a quarter of a century - producing nothing but grief. Genscher ended up describing the Khomeinist regime as a trap whose embrace is best avoided.

To be sure, Obama can't suddenly declare that he no longer wants direct, unconditional talks. That would enrage his anti-war base. So, he is trying to bring the camel down from the roof, as the Persian proverb has it, without appearing to have made a U-turn.

Obama no longer talks of "meeting them anywhere, anytime." Instead, he speaks of engaging Iran "at a time and place of my choosing." His initial idea of talking to Ahmadinejad is also gone. Now, he says he'd talk to "appropriate Iranian leadership" (whatever that means).

Clearly, he has toned down the concept of "unconditional talks." He talks of "careful preparations," while his advisers say that he won't seek talks with Tehran until after the Iranian presidential election next summer. The idea is to deny Ahmadinejad a breakthrough with America that would bolster his re-election bid.

That Obama is rethinking his rash idea of unconditional talks with Tehran, even if that means alienating key allies, is a welcome development. His assertion that the Iranian problem can't be solved with "a knee-jerk reaction" is also welcome. Nevertheless, if the alternative is doing nothing, the new Obama position may prove more dangerous than the one he's trying to abandon.

That's because the clock is running out on those who wish to prevent the mullahs from building a nuclear arsenal. Last month, the International Atomic Energy Agency warned that Iran has speeded up its nuclear program. The IAEA says that Iran, in "a covert bid to expand its nuclear program, recently tested ways of retrieving highly enriched uranium from waste-reactor fuels."

Most experts agree that "the moment of truth" in Iran's nuclear standoff with the UN is likely to come during Obama's presidency - probably in 2010 or 2011. Unless Obama manages to stop the process before that, he could end up facing nuclear-armed mullahs. Then, the choice would be between acknowledging a fait accompli and using force to change it.

Obama urgently needs a credible policy for dealing with the Khomeinist threat. No one is asking for a knee-jerk reaction. But buying time (the mullahs' specialty) is no alternative, either.