WASHINGTON -- Ahmadinejad at Columbia provided the entertainment, but Sarkozy at the U.N. provided the substance. On the largest possible stage -- the U.N. General Assembly -- President Nicolas Sarkozy put Iran on notice. His predecessor, Jacques Chirac, had said that France could live with an Iranian nuclear bomb. Sarkozy said that France cannot. He declared Iran's nuclear ambitions "an unacceptable risk to stability in the region and in the world."

His foreign minister, Bernard Kouchner, had earlier said that the world faces two choices -- successful diplomacy to stop Iran's nuclear program or war. And Sarkozy himself has no great hopes for the Security Council, where China and Russia are blocking any effective action against Iran. He does hope to get the European Union to join the U.S. in imposing serious sanctions.

"Weakness and renunciation do not lead to peace," he warned. "They lead to war." This warning about appeasement was intended particularly for Germany, which for commercial reasons has been resisting U.S. pressure to support effective sanctions.

Sarkozy is no American lapdog. Like every Fifth Republic president, he begins with the notion of French exceptionalism. But whereas traditional Gaullism tended to define French (BEG ITAL)grandeur(END ITAL) as establishing a counterweight to American power, Sarkozy is not adverse to seeing French assertiveness exercised in conjunction with the United States. As Kouchner put it, "permanent anti-Americanism" is "a tradition we are working to overcome."

This French about-face creates a crucial shift in the balance of forces within Europe. The East Europeans are naturally pro-American for reasons of history (fresh memories of America's role in defeating their Soviet occupiers) and geography (physical proximity to a newly revived and aggressive Russia). Western Europe is intrinsically wary of American power and culturally anti-American by reflex. France's change from Chirac to Sarkozy, from Foreign Minister Dominique de Villepin (who actively lobbied Third World countries to oppose America on Iraq) to Kouchner (who supported the U.S. invasion on humanitarian grounds) represents an enormous shift in Old Europe's relationship to the U.S.

Britain is a natural ally. Germany, given its history, is more follower than leader. France can define European policy, and Sarkozy intends to.

The French flip is only one part of the changing landscape that has given new life to Bush's Iran and Iraq policies in the waning months of his administration. The mood in Congress also has significantly shifted. Continued...