Kabul, Afghanistan ? Taliban insurgents once derided as a ragtag rabble unable to match U.S. troops have transformed into a fighting force – one advanced enough to mount massive conventional attacks and claim American lives at a record pace.

The U.S. military suffered its 101st death of the year in Afghanistan last week when Sgt. 1st Class David J. Todd Jr., a 36-year-old from Marrero, La., died of gunfire wounds while helping train Afghan police in the northwest. The total number of U.S. dead last year – 111 – was a record itself and is likely to be surpassed.

Top U.S. generals, European presidents and analysts say the blame lies to the east, in militant sanctuaries in neighboring Pakistan. As long as those areas remain havens where fighters arm, train, recruit and plot increasingly sophisticated ambushes, the Afghan war will continue to sour.

“The U.S. is now losing the war against the Taliban,” Anthony Cordesman, of the Washington-based Center for Strategic and International Studies, wrote in a report last week. A resurgent al-Qaida, which was harbored by the Taliban in the years before the Sept. 11 attacks, could soon follow, Cordesman warned.

Cordesman called for the U.S. to treat Pakistani territory as a combat zone if Pakistan does not act. “Pakistan may officially be an ally, but much of its conduct has effectively made it a major threat to U.S. strategic interests.”

An influx of Chechen, Turkish, Uzbek and Arab fighters have helped increase the Taliban’s military precision, including an ambush by 100 fighters last week that killed 10 French soldiers, and a rush on a U.S. outpost last month by 200 militants that killed nine Americans.

Multidirection attacks, flawlessly executed ambushes and increasingly powerful roadside and suicide bombs mean the U.S. and 40-nation NATO-led force will in all likelihood suffer its deadliest year in Afghanistan since the 2001 invasion.

French President Nicolas Sarkozy, who rushed to Afghanistan after the French attack, warned Thursday that “terrorism is winning.”

“Military sanctuaries are expanding in the (Pakistani) tribal areas,” Gen. David McKiernan, the American four-star general in charge of the 50,000-strong NATO-led force here, told The Associated Press last week.

McKiernan has called for another three brigades of U.S. forces – roughly 10,000 troops – to bolster the 33,000 strong U.S. force here.

Complicating relations between the Afghan government and the U.S., last week a joint Afghan-U.S. military operation in Herat province killed about 90 civilians, President Hamid Karzai’s office says. The U.S. said it was investigating.

About 188 international soldiers have died in Afghan-istan this year, including the 101 Americans, according to an Associated Press count. This year’s toll is easily on track to surpass the record 222 international troop deaths in 2007.

According to Defense Department statistics released Sunday, at least 508 members of the U.S. military have died in Afghanistan, Pakistan and Uzbekistan as a result of the U.S. invasion of Afghanistan in late 2001. Of those, the military reports 362 were killed by hostile action.