Afghan War In Depth:Night Mission's Fiery End

Nine U.S. commandos were killed early Tuesday when their Blackhawk helicopter went down in Zabul Province,Afghanistan.Taliban militants said they shot it down,but the NATO defense alliance said there was no evidence of enemy fire in the area.Helicopter crashes are distressingly common in the dusty,mountainous country.
There is no room for pilot or maintenance crew error in the harsh conditions.
The special operations troops were reportedly on a night mission,which adds to the danger of flight.Another NATO soldier and a civilian were injured in the crash.Four U.S. Navy SEALs were among the dead;the other five were U.S. Army troops.Several SEALs have been killed on previous missions.The worst helicopter crash of the war occurred in 2005,when 16 Americans died.
Located in Southeast Afghanistan,Zabul is notoriously dry and windy,with farming limited to a few irrigated valleys.It is populated by tribes fiercely loyal to the Taliban militants.Zabul borders Pakistan to the south,and Kandahar Province to the west.
NATO and Afghan forces,including U.S. Marines,are trying to flush the militants out of the greater Kandahar area,which is the militant heartland,while intercepting militants at checkpoints that surround the city and conducting raids to capture or kill their leaders.Some success has been reported,such as increasing commerce and movement,building up the Afghan police,clearing the key Argandhab Valley and returning 85% of it to Afghan control.
On the other hand,the militants have been increasing their presence in the north of the country while NATO concentrates on the more populous south.U.S. Marines involved in the southern operations include the 1st and 2nd Marine Divisions,sustaining many casualties in Helmand Province,which borders Kandahar Province.