KABUL – The city was in a full clamp down for the big gathering as heavily armed convoys shuttled the president, diplomats and military brass to the event.

Everyone who is anyone in Kabul was gathering for the ceremony at a heavily guarded military base where Gen. Stanley McChrystal, a former top special operations commander, took charge of nearly 90,000 U.S. and NATO troops in Afghanistan.

McChrystal told the gathering on Monday that the US and coalition forces must protect Afghan civilians from all kinds of violence.

“The Afghan people are at the center of our mission. In reality, they are the mission. We must protect them from violence, whatever its nature,” McChrystal said. “But while operating with care, we will not be timid.”

McChrystal takes charge in Afghanistan at a fateful turn in the US military presence here as an increase of some 21,000 troops gets underway and the US braces for a full-on offensive against the Taliban in the south.

It’s going to be a long, hot summer in Afghanistan.

And President Hamid Karzai is turning up the heat on U.S. forces to prevent civilian deaths. It is a problem that has plagued the US operation and caused wide-spread anger among Afghans about the US presence here.

The death of what the Afghan government claims was 140 civilians during May 4 air strikes in the Farah province is largely perceived as the tragedy that cost General David McKiernan his job and effectively ended his military career. A US military inquiry stated that the number of civilian casualties in Farah was lower, and estimated that the attacks killed approximately 30 civilians and some 60 Taliban militants.

GlobalPost interviewed the governor of Farah Province, Roohul Amin, by phone Sunday night from inside the governor’s palace in Farah. He said that the US forces were “working very hard” to be more careful about civilian deaths.

“The truth of this is the Taliban has intentionally put civilians in the middle of the fighting. They know what they are doing,” said Amin.

McChrystal is known as a bit of a wild man and is expected to take a more “unconventional” approach to taking on the Taliban. That may mean less air strikes and more targeted assassinations, observers here say. It is an approach grows out of his long experience with special forces and elite military units like Navy SEALs and Army’s Delta Force.

And these “unconventional” approaches can come with risks of their own.

Like we said, it’s going to be a long, hot summer.

U.S. Gen. Stanley McChrystal, right, salutes during his assumption of a command ceremony as the head of U.S. and NATO forces in Afghanistan in Kabul. (AP Photo/Ricardo Mazalan)