President Obama has put securing Afghanistan near the top of his foreign policy agenda, but "victory" in the war-torn country isn't necessarily the United States' goal, he said Thursday in a TV interview.

"I'm always worried about using the word 'victory,' because, you know, it invokes this notion of Emperor Hirohito coming down and signing a surrender to MacArthur," Obama told ABC News.

The enemy facing U.S. and Afghan forces isn't so clearly defined, he explained.

"We're not dealing with nation states at this point. We're concerned with Al Qaeda and the Taliban, Al Qaeda's allies," he said. "So when you have a non-state actor, a shadowy operation like Al Qaeda, our goal is to make sure they can't attack the United States."

The United States and Afghanistan are struggling to shore up security in the country, amid increasing violence. The Obama administration this year stepped up U.S. military operations in the country as the U.S. military presence begins to wind down in Iraq.

"We are confident that if we are assisting the Afghan people and improving their security situation, stabilizing their government, providing help on economic development ... those things will continue to contract the ability of Al Qaeda to operate. And that is absolutely critical," Obama told ABC News.

Rising casualties in Afghanistan are raising doubts among U.S. allies about the conduct of the war, forcing some governments to defend publicly their commitments and foreshadowing possible long-term trouble for the U.S. effort to bring in more resources to defeat the Taliban.

Pressure from the public and opposition politicians is growing as soldiers' bodies return home, and a poll released Thursday shows majorities in Britain, Germany and Canada oppose increasing their own troop levels in Afghanistan.

Europeans and Canadians are growing weary of the war -- or at least their involvement in combat operations -- even as Obama is shifting military resources to Afghanistan away from Iraq.

The United States, which runs the NATO-led force, has about 59,000 troops in Afghanistan -- nearly double the number a year ago -- and thousands more are on the way. There are about 32,000 other international troops in the country.

The new U.S. emphasis on Afghanistan has raised the level of fighting -- and in turn, the number of casualties. July is already the deadliest month of the war for both U.S. and NATO forces with 63 international troops killed, including 35 Americans and 19 Britons. Most have been killed in southern Afghanistan, scene of major operations against Taliban fighters in areas that had long been sanctuaries.

The leaders of the largest contributors to the coalition find themselves having to justify both their reasons for deploying troops and their management of the war effort. Britain, Italy and Australia are among those adding forces ahead of Afghanistan's Aug. 20 presidential election.

They say a Western pullout at this time would enable a resurgent Taliban to take over the country and give Al Qaeda more space to plan terror attacks against the West. Some emphasize humanitarian aspects of their missions, like development aid and civilian reconstruction.

The Associated Press contributed to this report.