Many factors contributed to this failure. Let us look at some of the most important ones.
- The enemy was very popular in South Vietnam. This reduced the South Vietnamese desire to fight.
- The South Vietnamese government was unpopular and was ineffective.
- The US was trying to win the "hearts and minds" of the populace. This is a very hard thing to do through military power.
- The US military was not allowed to figure an unlimited war. Political leaders had to be wary of public opinion in the US and around the world. This led them to put major limits on what the military could do.
- The enemy was very difficult to find as much of the war was a guerrilla insurgency. This made military victory difficult and undercut the morale of the soldiers.
- The draft also undermined morale and reduced military efficiency.
- As US public opinion turned against the war, there was less political support for the war both within the government and outside of it.