On Wednesday, the White House said it would be "unproductive and unhelpful" for Democratic congressional leaders to visit Iran. House Foreign Affairs Committee Chairman Tom Lantos had said earlier he was "ready to go" to Teheran and that House Speaker Nancy Pelosi "might be" willing as well. It does not seem that such a trip will come about. Pelosi, whose office has denied that she plans a Teheran visit, said she found Iranian President Mahmoud Ahmadinejad's denials of the Holocaust and threats to destroy Israel "to be so repulsive that they're outside the circle of civilized human behavior." Nonetheless, she said the willingness of Lantos, a Holocaust survivor, to meet with Ahmadinejad "speaks volumes about the importance of dialogue." Congressional leaders are certainly speaking volumes with their actions and words, but what are they really saying? We have no comment on the age-old debate between American branches of government over the right to conduct foreign policy. Yet the issue is not just a matter of rights, but of wisdom, and of the impact that particular battles over strategy might have on American effectiveness in the world. The choice of Pelosi and Lantos to visit Damascus, for example, and the latter's desire to go to Teheran illustrate what might be called an obsession with the "importance of dialogue." Is Pelosi really claiming that there has been a lack of dialogue with Iran? Say what you will about the Bush administration, but it is difficult to argue that it has approached the Iranian challenge with excess haste. For years now, ever since it became evident that Iran had lied to the IAEA about its nuclear program, the US backed an almost endless European dialogue with Teheran. Throughout, Iran has been offered extensive support for a verifiably civilian nuclear program, enhanced trade, the lifting of sanctions, and, probably, different forms of guarantees for the current regime - all contingent only on giving up the capability to produce nuclear weapons. Yet as the offers have become sweeter and more concrete, the mullahs have become increasingly defiant. Policies of isolation and dialogue do not mix. It is not just the Bush administration, but unanimous votes of the UN Security Council that have effectively pronounced the end of the time for dialogue. Even the Europeans - even Russia and China - concluded that the way to respond to Iran's rejection of the first batch of sanctions was with stronger ones. None of this is to say that Pelosi, Lantos and other Democrats find the Iranian regime any less repulsive or dangerous than does the White House and its allies. But the question must be asked about the Democrats' strategic sense. What is the message that Congressman Lantos thinks he can better deliver to this regime that the entire international system cannot? And what is the danger that the fact of such a visit would directly undermine international efforts to force the regime to back down? Democrats have every right to advocate foreign policy of their own. What is not clear is what they are suggesting as an alternative to the international consensus that a regime that is supporting terrorism, making genocidal threats and developing weapons of mass destruction must be confronted. If anything, the Bush administration, by so fully delegating Iran policy into European hands, has failed to galvanize the international community into taking sufficient action. In this context, Pelosi and the Democrats could influence world events much more positively and effectively if they joined forces with the White House on Iran. The Democrats should be pushing for harder and faster sanctions on Iran, since this is the only conceivable way to stop an Iranian bomb without resorting to military action. Europe would be more receptive to a call for draconian sanctions if it came from both sides of the American aisle. Politically, the Democrats would demonstrate willingness to stand together against a common threat, and inoculate themselves from accusations that they are "soft on Iran." Substantively, they could show that they take their own belief in nonmilitary measures seriously, and want to put them into practice as strongly as possible.