Months before the military was accused of killing innocent civilians in Iraq, the No. 2 U.S. general in the region was working to change how American troops approached battle and the Iraqi civilians so often caught in the line of fire.

Watch for more of David Kerley's interview on both "World News Tonight" and "Nightline" this evening.

Lt. Gen. Pete Chiarelli took command in January, and since then he has told soldiers they need to change their approach to their work.

"We are creating many, many more enemies than we are ever reducing," he said.

By his estimate, 30 percent of Iraqis have said they believe it is the American troops pose are the greatest threat to their security. He believes cultural insensitivity and the misuse of deadly force is turning many Iraqis against the United States.

"We are made to deliver force. That's what we train our Army to do and that's what you, the American people, want an Army to do," he said. "But we find ourselves in an environment unlike any I've ever been in before."

All troops are now receiving mandatory core values training, but before that began, the general was urging soldiers to act more like police officers, making sure they only target the bad guys. For veterans, this message may not always be a welcome one.

"Well, some of them probably don't particularly care for it. Some of them really feel you can shoot your way out of this thing. I don't believe that," he said.

Chiarelli said his efforts have paid off. The number of times soldiers have fired on perceived threats is down by one third, and the number of innocent Iraqis dying at the hands of U.S. forces has dropped in half.