ERLIN -- European leaders, increasingly irritated by the Bush administration, feel they are coming to a moment of truth about themselves and their relationship with Washington.

American contempt for a weak Europe is producing pressure for more unity, more outspoken independence and a clearer understanding that Europe must spend more money on its military forces if Washington is going to take it seriously.

Real interests are diverging, and years of talk about tensions and resentments have crystallized into a sudden perception that the relationship itself has changed.

On fundamental issues like the International Criminal Court, the Kyoto environmental treaty and the crisis in the Middle East, even strongly pro-American leaders like the British prime minister, Tony Blair, and the German foreign minister, Joschka Fischer, are openly differing with America with a public bluntness that would have been unthinkable five years ago or in the weeks after Sept. 11.

There is shock over the way Washington handled the court issue at the United Nations, puzzlement over the concentration on Iraq as the Israeli-Palestinian relationship deteriorates and confusion over how to move forward in the Middle East with Yasir Arafat ruled out but no mechanism to establish another Palestinian leadership.

And there is dismay that Secretary of State Colin L. Powell, a European favorite, is losing key battles to the conservatives who seem to have won Mr. Bush's ear and who regard European criticism as the whining of weaklings. The moral leadership that President Bush was granted and exercised after Sept. 11 has been "frittered away," a senior European official said. Renewed American unilateralism is giving weight to the old French idea of the European Union as a counterbalance to Washington.

Even more striking, some Europeans are talking about finally putting their money where their mouths have been for so long on defense spending, understanding that the superpower in Washington will only take them seriously when they can project hard power to back up their foreign policies.

A more competitive relationship with Washington, some argue, would be healthier, because it would be more realistic, and it would also help respond to increasingly anti-American views among their publics.

"Solidarity has to be a two-way highway," said another senior German official. "Unless, of course, you want to strengthen those who say we must develop our own mechanisms and we can't rely on the United States in all cases."

ONE of the texts helping to define the European discussion is a long article in Policy Review, an American quarterly published by the conservative Hoover Institution (www.policyreview.org). The article, "Power and Weakness," by Robert Kagan, is circulating by e-mail and causing European elites to see themselves more as Washington sees them as powers who use multilateralism as a kind of weapon to restrain the superpower.

The Atlantic is fundamentally divided over attitudes to power, Mr. Kagan asserts. The Europeans, to escape their bloody history, are sharing sovereignty in the European Union, "moving beyond power into a self-contained world of laws and rules and transnational negotiation and cooperation."

The United States, as a traditional nation-state bestriding the world and seeing threats all around, is "exercising power in the anarchic Hobbesian world where international laws and rules are unreliable and where true security and the defense and promotion of a liberal order still depend on the possession and use of military might."

So, Mr. Kagan argues, behind the bitterness of the policy disputes are deep differences in values and politics, stemming from different histories and attitudes toward power and threat. The continental drift isn't a function of one administration, although the tone may change, with Mr. Bush more blunt than the ever-emollient Bill Clinton.

The resolution, Mr. Kagan believes, is in a Europe that will commit more money and resources to the military to the ability to project power, at least through the Balkans and perhaps the Middle East. Only then will Washington take Europe more seriously. Mr. Kagan says he would like Europe to take such steps, but doubts that it will.

While he has his critics, he has also found support from prominent Europeans.

Pascal Lamy, the European Union trade commissioner, thinks Mr. Kagan has it right: "Stop pretending that the United States and Europe share a common view of the world, recognize we have different world views and interests and then manage our relations." To Americans, he said, "Europeans seem a bunch of unprincipled wimps who complain and embrace multilateralism out of weakness, because unilateralism is out of reach." Mr. Kagan "pushes the debate to the next question: how far will Europeans go to defend their rule-based systems? Will we take risks, lose lives and pay more? That's the real question, which we Europeans have carefully organized ourselves not to ask."

François Heisbourg, who runs the Foundation for Strategic Research in Paris, says Mr. Kagan has lumped together the more martial French and British with those European countries who flee from power, whom the French call "les Woodstockians." Still, he says, "no academic piece in this realm has generated quite as much heat and interest since Samuel Huntington's `Clash of Civilizations' article in 1993 or Francis Fukuyama's `End of History' in 1989."

But he disagrees. Multilateralism is not for the weak, but also for the strong, he said. "America became a superpower through multilateralism and the Atlantic Charter in 1941. It is a superpower not by its military and economic weight but by virtue of sustaining permanent alliances, and multilateralism is at the heart of those alliances."

Americans are also not alone hunting bears in the woods, as Mr. Kagan suggests. Mr. Heisbourg argues that Al Qaeda is more like a mutating virus than a bear, and it requires a varied quiver to fight, including intelligence, counter-terrorism and financial expertise areas where Europe excels.

Josef Joffe, editor in chief of Die Zeit, which has excerpted Mr. Kagan's piece, says even the underfunded European defense arm a proposed force of 60,000 is designed to keep a peace, not fight a war. Still, he said, European soldiers and pilots are fighting effectively in Afghanistan. "It is also true," he said, "that multilateralism is the weapon of the weak, and that there is an unarticulated power game going on, with the Europeans trying to restrain the United States like the Lilliputians did Gulliver, through international regimes." But this is an old theme, dating to the 60's.

Jeffrey Gedmin, director of the Aspen Institute Berlin, said he is an "Atlanticist" and is troubled. Debates about the alliance have swirled since Communism collapsed, and then, he said, "suddenly Kagan writes a piece that says, in a sort of primitive way, `Extra, extra, we're different.' And we who thought that more talk and more understanding can bridge the gap are being told, `No, forget it, you won't, it's about history and culture,' and that's breathtaking."

"They need us less in relative terms after the cold war and in relative terms, after 9/11, we need them less, too," Mr. Gedmin said of the Americans. "And Kagan says, `Maybe that's O.K.,' but I don't know if it's O.K. I have a real fear of decoupling."