U.S. in Longest War Since Vietnam

WASHINGTON -- The five-month war in Afghanistan has become the U.S. military's longest sustained engagement since Vietnam, with an elusive enemy sheltered in strange and savage terrain.

Still, few Americans have died in combat. Although the current Operation Anaconda is an exception, most of the fighting has been conducted with precision weapons dropped by airplanes and small special forces units working with Afghan militias.

No other war will be exactly like the one in Afghanistan, analysts and military officials say. But the battles have had many features that probably will be repeated in the war on terrorism and in future conflicts.

"You really have a trend there," says military analyst Michael Vickers of the Center for Strategic and Budgetary Assessments. "We're fighting asymmetrically, using areas where we can hit the enemy and they can't hit us."