Bagram, Afghanistan ? The new commanding general of U.S. and coalition forces in Afghanistan vowed Tuesday to keep up the fight against terrorism, but said bringing peace to this war-shattered nation would not be easy.

But with rebels and al-Qaida fighters still launching hit-and- run attacks on coalition troops, Afghan soldiers and aid workers, Maj. Gen. John R. Vines said maintaining security would not be easy.

“Some 25 years ago, as Afghanistan was racked by war, the world looked the other way. Your presence here today reflects a commitment not to repeat that mistake,” the 53-year-old Vines said after taking over Lt. Gen. Dan K. McNeill.

“We’re here because our governments have committed to helping Afghanistan establish itself as a peaceful, prosperous nation. The job will not be easy.”

The handover ceremony took place on a runway lined with helicopters at Bagram Air Base, the headquarters of 11,500 coalition troops, 8,500 of them American, deployed in the country.

Senior Afghan commanders attended the ceremony, as did Afghan Foreign Minister Abdullah and diplomats including U.S. Ambassador Robert Finn.

U.S. military spokesman Col. Rodney Davis called Tuesday’s change in leadership “routine.” American commanders and soldiers in Afghanistan regularly serve tours-of-duty that don’t exceed a year.

The handover coincides with a shift in combat ground forces. About 4,000 troops from the U.S. Army 10th Mountain Division, based at Fort Drum, N.Y., are replacing an equivalent number of soldiers from the U.S. Army 82nd Airborne Division, based at Fort Bragg, N.C., Davis said.

Both divisions fall under the umbrella of the 18th Airborne Corps, which McNeill still heads. Vines is due to take over command of the 18th Airborne this summer, McNeill said.

Vines has been in Afghanistan for nine months. As commander of the 82nd Airborne Division, he was responsible for tactical combat missions.