By including Iran last week in the "axis of evil," President Bush put an end to one of the most unlikely U.S. initiatives to emerge after the Sept. 11 attacks: the administration's delicate exploration of closer ties with Tehran.

Bush's language was more provocative than some State Department officials wanted. But it reflected a recognition across the administration that the cautious American opening, which included consideration of easing some economic sanctions on Tehran, could not be sustained after series of jolts last month that the United States blamed on Iran.