Five miles from the muddy bazaar where smiling merchants offered tea to U.S. Army Col. David Haight and insisted that outsiders were making all the trouble, a deadly reception had been prepared for his five-vehicle patrol.

A U.S. pilot had spotted men burying what turned out to be a bomb by the road where Haight was stopping to ask how he could help poor farmers and jobless youths who were desperate for any kind of work, including setting explosives for the Taliban .

The stocky combat veteran from Fairfax, Va. , wasn''t buying what he was hearing about all the troublemakers being outsiders.

"The IED" — improvised explosive device — "that was put on the road down there? The guys are from Baraki Barak," Haight said as he and his men made their way past dingy shops and fruit carts, their fingers rarely straying from the triggers, grimy children gamboling noisily in their wake.

Down the road, U.S. military engineers found and blew up the remote-controlled bomb.

The encounter illustrates the distrust and anger that U.S.-led forces face as the Obama administration tries to stem the Taliban -led insurgency by sending more American troops to Afghanistan and ramping up a strategy to start making good on years of empty U.S. vows to better the lives of ordinary Afghans.

The region where Haight''s 3rd Brigade Combat Team of the 10th Mountain Division , from Fort Drum, N.Y. , deployed six weeks ago is shaping up as one of the most crucial proving grounds for the revamped U.S. counterinsurgency strategy.