The U.S. military made public new guidelines Monday for its troops in Afghanistan, battlefield rules that seek to reduce the number of civilian casualties in an increasingly deadly war.

Civilian deaths caused by U.S. and NATO military operations have long been a source of friction between President Hamid Karzai and the international force. Such deaths alienate Afghan villagers, causing a loss of support for the international mission and the U.S.-backed Afghan government.

U.S. Gen. Stanley McChrystal, who took over last month as the commander of U.S. and NATO forces, has said he wants his troops' first priority to be protecting Afghan civilians, not using massive fire power. McChrystal's new guidelines went into effect last week, and officials released a declassified version Monday.

The three directives for U.S. and NATO forces, posted on the military's Facebook page as part of a longer statement, are:

— Airstrikes must be very limited and authorized but can be used in self-defense if troops' lives are at risk.

— Troops must be accompanied by Afghan forces before they enter residences.

— Troops cannot go into or fire upon mosques or other religious sites. This is already U.S. policy.

In the statement announcing the guidelines, McChrystal said the Taliban cannot defeat U.S. and NATO forces but that "we can defeat ourselves" by alienating the Afghan people.

"This is different from conventional combat, and how we operate will determine the outcome more than traditional measures, like capture of terrain or attrition of enemy forces," the new order says. "We must avoid the trap of winning tactical victories — but suffering strategic defeats — by causing civilian casualties or excessive damage."

Sarah Holewinski, the executive director of the Washington-based Campaign for Innocent Victims in Conflict, said McChrystal's new guidelines are what "U.S. and allied troops should have been doing from the beginning."

"Whether it's the media coverage, Karzai's pleas, civilian protests or top military brass taking seriously 'hearts and minds,' it seems something is finally getting through, now eight years into the conflict," Holewinski said. "I hope we continue to see this kind of effort made to dignify these tragedies when protection efforts fail."

McChrystal has made a point of advertising his efforts to achieve a "cultural shift" in the military since taking over the command.

An Associated Press reporter observed one such example last month at Kandahar Air Field during a daily video teleconference update with regional generals from around the country.

A military briefer told McChrystal that NATO forces locked in battle with Taliban militants had called in an airstrike after the insurgents had retreated into a mud-brick compound. The bomb destroyed the compound, killing the fighters, the briefer said.

McChrystal turned on his microphone and asked a question he hopes is now on the mind of every military commander in Afghanistan: How did the troops know there were no civilians in the compound?

"They could have stopped at any compound," McChrystal said. "It could have been filled with kids."