Five months after it began, the fighting in Afghanistan has become what the United States claimed it was all along: a war on international terrorism fought by an international coalition.
With more than a half-dozen countries as diverse as Norway, France, Germany, and Canada involved in what Pentagon officials say is the largest ground combat operation so far, the war in Afghanistan is now closer to being the world's war against terrorism.
The latest fighting, which has already cost the US more casualties than the rest of the war, suggests a recalibrating of the original go-it-alone strategy.
"The Americans have learned that it is better not just to talk about a coalition, but to show that there is a coalition on the ground," says Bernhardt May, deputy director of the influential German Foreign Policy Society in Berlin. "We have to work on the coalition politically."
Coalition fighters now make up more than 10 percent of a ground force the Pentagon says numbers about 2,000, of which more than 800 are Americans mainly from the 101st Airborne and 10th Mountain divisions. The mostly European coalition soldiers include special operations units with specific training in winter mountain fighting.
The troops - in the largest offensive since the war began in October - have engaged with Al Qaeda and Taliban fighters in Gardez, in extremely high, snow-covered mountains in the eastern part of Afghanistan. Known as Operation Anaconda, ground troops have surrounded pockets of Al Qaeda fighters and are blocking all escape routes. Meanwhile, US bombers are now pummeling the caves where the terrorists are holed up.
It is to the US's advantage militarily to be able to call on allied forces with special training, as their deployment in the mountains demonstrates. Beyond that, the US knows Al Qaeda has cells in up to 60 countries. Taking them out will require cooperation, which in turn requires good political relations.
The stronger the link that can be demonstrated in those countries, the stronger the support is among Europeans, says Tomas Valasek, a senior analyst with the Center for Defense Information in Washington. "But when the US is seen moving forward with motivations other than simply terrorism - as in the case of Iraq - the support drops off."
While no one suggests the US military chose this battle to make a political statement, the end result could nevertheless be a coalition more comfortable with US command of the war.
Boosting coalition partcipation at this time "is not any kind of political move to address some secondary goal, this is far too serious," says Christopher Langton, a military analyst at the International Institute for Strategic Studies in London. Still, Col. Langton says he expects to see considerable positive reaction in countries like Norway and France, which he says have special forces for mountain fighting assigned to the battle.
French Premier Lionel Jospin sounded pleased to announce Tuesday morning on French radio that bombers based in Kyrgyzstan and on the aircraft carrier Charles de Gaulle were striking Taliban positions. "We are playing our part in this offensive," he said. "The forces that remain from the terrorist network must be broken, and our determination in this respect is total."
The inclusion of coalition forces also reflects the Pentagon rethinking its strategy following the December battle for Tora Bora, military analysts say. In that battle, the US dropped in only a few special forces troops to guide airstrikes. They relied almost exclusively on local Afghan warlords to run the ground operation.
The Pentagon was led to believe that not only some 2,000 Al Qaeda fighters were cornered in that operation, but that its top leadership - including Osama bin Laden - would be taken as well. But it gradually became clear that Afghan fighters serving the US mission on the ground had allowed many enemy fighters to flee.
This time the US is doing more of the ground work to get the job done right - and is also calling on allied forces to help.
"Until the end of last year, ground troops were doing reconnaissance and guiding airstrikes, and it was hard to involve troops from other countries," says retired French Gen. Jean-Vincent Brisset. "Now they are fighting a relatively classic ground battle, and the Americans can use the people who have just been waiting for the chance."
Still, the new-found harmony between the US and its allies may not last beyond the fighting in Afghanistan, some analysts say.
"This [joint warfare] will help," but it comes late to repair the rift caused by the first months of operation," says Mr. Valasek.
For one thing, European involvement is still not as "robust" as the allies would like, he says.
But differences are going to continue to surface over the future direction of the war - and especially over any attack on Iraq.
"That is where the US and Europe start parting ways," Valasek says.
Official European enthusiasm for the war could also be affected if any of the allied forces take casualties.
Others wonder how Europe will respond if it the world's Muslim populations more solidly associate it with a war being fought against Al Qaeda forces - which include fighters from perhaps a dozen Muslim countries.
So far, the German and French populations are showing little interest in their military involvement, though interest is high in Norway.
In Germany, where the question of military involvement abroad has been especially sensitive, Dr. May said he is "puzzled and surprised" by the lack of reaction to the news that German special forces are involved in combat for the first time since World War II.