For years, U.S. military officials coming to Europe have sounded a constant theme: Europeans need to spend more on defense and do more to shoulder the burden of the Atlantic alliance. And routinely the message has been politely listened to, and then ignored.

But in the post-September 11 defense environment, some analysts are seeing hints of change. The recent NATO summit in Prague ended with what U.S. and NATO officials called unofficial promises from several European countries to increase their military spending. Most NATO members have signed on to a list of new commitments -- including leasing transport planes and investing in precision-guided munitions -- that could require significant outlays of cash.

"The tide has turned in terms of the attitude towards defense," said George Robertson, the NATO secretary general and long a vocal proponent of spending increases.

Defense Secretary Donald H. Rumsfeld, in a news conference in Prague before his departure, was less convinced there had been a shift in thinking. "I'm never satisfied -- it's genetic with me," he said. "I'd like to see them inject a sense of urgency." In addition to spending more, he said, there is also a need to refocus spending priorities toward the "real threats" that have emerged since the terrorist attacks in the United States.

Interviews with diplomats and defense analysts since the Prague summit suggest the reality may be somewhere between these two views. Promises made at Prague might have been genuine statements of government leaders' intentions, they said, but now back home, those leaders have to confront tight budgets, shrinking resources and competing demands for the same money.

One obstacle is the budgetary calendar. Defense spending, particularly for major purchases, requires planning years ahead, but it is difficult for governments to pledge money beyond the upcoming fiscal year.

A NATO ambassador in Brussels said, "I think the trend is in the direction of doing more -- but exactly how much more will be determined by the new budget," which in his country will not be approved until January.

NATO had set 2 percent of gross domestic product as the minimum countries should spend on defense. But the majority of NATO countries are not close to that. Germany, for example, spends about 1.5 percent, according to NATO. The figure for defense spending is not likely to change soon, diplomats said. "Defense is not a popular thing to spend money on," the NATO diplomat said.

Rather than increasing defense spending, most countries will simply end the annual reductions in their military budgets that began with the fall of the Berlin Wall in 1989. Then, governments were looking for a financial "peace dividend" with the end of the Cold War.

The decline in defense budgets generally ended close to the Sept. 11, 2001, attacks and coincided with the return to power of center-right governments in several European countries. France has announced a substantial increase in defense spending, as have Portugal and Hungary. "In most countries, the trend toward decreasing has been replaced by a stabilization," said Francois Heisbourg, a French defense analyst. Still, he said, "Quite surprisingly, some significant countries, like Italy and the Netherlands, are getting into fairly deep cuts."

The United States is spending about $355 billion per year on defense, with the Bush administration's latest increases factored in, but Europe and Canada combined spend about $160 million, or less than half of the U.S. defense budget.

The problem, analysts said, was not so much that Europe and Canada together were spending less, but were spending what they had on the wrong things, allowing the gap in military technology to grow between the United States and its allies.

For example, said one NATO official, the United States has about 550 air-to-air refueling tankers. Europe has 100. The United States has 300 planes for airlifting large cargo; Europe has four. "To spend more money is necessary, but you've got to spend it on the right things," this official said.

"We've got far too many tanks," Robertson said in Prague. "We've got far too many fighters and attack aircraft. We've got far too many troops that are not deployable."

At the NATO summit, an effort was made to produce a set of "consortium" areas in which countries, especially smaller ones, could pool their resources. But officials acknowledge privately that such arrangements have limits, because sovereignty, history and pride mean that most countries do not want to depend upon others for certain key aspects of their national defense. Every country, for instance, wants to have its own air force to protect its airspace, even if it would be cost-effective to have only a few countries with fighter jets guarding a common European airspace.