On March 8, 1965, the United States sent its first "official" combat troops into Vietnam. An aerial bombing plan ordered by U.S. President Lyndon Johnson began at this time against North Vietnam called Operation Rolling Thunder. It was supposed to last two months, but went on for three whole years. The main U.S. weapon used in the war against Communist North Vietnam was the B-52 Bomber, which could fly so high that no one could see or hear them coming. B-52 Bombers were top technology since the U.S. was the most advanced nation in the world at that time. Between 1965-1973, the U.S. dropped 8 million tons of bombs on Vietnam. Another disturbing weapon the U.S. used was called napalm. It was a sticky gel dropped from the air that caused severe burns on all victims.The strategies on the Vietnamese side were very simple, yet effective. There would be more hit and run attacks and ambushes than organized battles. A huge problem for the U.S. in this war was the landscape and environment. Vietnam is full of jungles, making it very hard to find the enemies during warfare. It was hard to tell which side the soldiers were on and booby traps were everywhere. This war was a brutal air and ground battle, with the U.S. losing the war and pulling out in 1973.