U.S. took too long to cut Afghan casualties: Mullen

KANDAHAR AIR FIELD, Afghanistan (Reuters) - The United States may have taken too long to cut Afghan civilian casualties but even junior troops now understand protecting ordinary Afghans is paramount, Washington's top military officer said on Friday.

After visiting military bases in southern Afghanistan, the scene of major operations by thousands of U.S. Marines and British troops, Admiral Mike Mullen gave an upbeat assessment of the prospects for success against the Taliban.

Mullen said he was pleased the Marines had not caused any civilian casualties in their push into the Helmand River valley over the past few weeks and British forces had reported very few in their simultaneous operation further north.

The issue of civilian casualties caused by U.S. and NATO operations, particularly air strikes, became a source of increasing outrage and frustration among ordinary Afghans and their leaders over the past year.

Mullen, chairman of the U.S. Joint Chiefs of Staff, told reporters traveling with him the lesson that civilian casualties had to be addressed had probably not been learned quickly enough.

"We did kill too many civilians," he said. "One is too many."

U.S. Army General Stanley McChrystal, the new U.S. and NATO commander in Afghanistan, issued a directive this month stressing the importance of avoiding civilian casualties and limiting the use of airpower against residential compounds.

Mullen said troops were clearly following that guidance in the current operations in Helmand province, a Taliban stronghold.

"Our troops right down to the very junior level understand what they need to do in a counter-insurgency -- they've got to protect the people," he said at the main NATO base outside the southern city of Kandahar.

DESERT LANDSCAPE

Earlier in the day, Mullen flew over the vast desert landscape of southern Afghanistan in baking heat to get a better feel for the war from U.S. and British troops and commanders.

Mullen, who serves as President Barack Obama's top military adviser, stressed the importance of winning the support of ordinary Afghans during town-hall style meetings with troops.

"We cannot succeed here without taking care of the Afghan people," he told U.S. soldiers at Forward Operating Base Ramrod, a site in Kandahar province fortified by giant tubs of sand topped with coils of barbed wire.

At Helmand's Camp Leatherneck, one U.S. Marine told Mullen the Afghan people he encountered "don't like us being here."

The young Marine said Afghans would take women and children indoors when they saw U.S. troops, although he added that "slowly but surely, they're starting to get used to us."

Mullen acknowledged some Afghans were hesitant, feeling they had been let down by the United States in the past and unsure that U.S. forces would stay to provide lasting security.

"Obviously they have to gain confidence in us," Mullen said.

Insurgent violence in Afghanistan has risen dramatically over the past few years as the U.S. military devoted the vast majority of its resources to the Iraq war under President George W. Bush.

Obama has made Afghanistan his top military priority and the United States is increasing its troop strength here this year by some 36,000 to 68,000. NATO nations and other U.S. allies have more than 30,000 troops in the country.

(Editing by Paul Tait)