The Vietnam war was stared by North Vietnam invaded south Vietnam in order to unify them to be on Vietnam. America joined in 1965 by sending 100,000 Marines and another 100,000 in 1966. Many other countries sent in troops as well. Many of the battles from the US and south Vietnamese troops were on the ground unlike the bombings form north Vietnam. The US troops were pushed back to the bottom of Vietnam during the Tet offensive launched by North Vietnam in 1968 but the US and south Vietnamese troops was able to push back and take more ground up to the border of China. China decided to aid the North Vietnamese troops and pushed the US and South Vietnamese troops back down to the 17 parallel.