Over all we did move out of the conflict because of domestic discontent at home, but the U.S. lost about 58,220 while the communist forces in the north (aka the Vietcong/NVA) lost close to 1000000 men in the fighting. So in all technicality we won the war because we defeated more enemies and we didn't admit defeat we signed an armistice ceasing all hostile actions until further notice.
The U.S. involvement in Vietnam did help stop communism from spreading to Thailand and Singapore. The goal was to stop the spread of communism in SouthEast Asia which the U.S. technically did. I am a strong believer in the Domino effect, and because of that I support the vietnam war. And here's a fun fact: The U.S. never lost any major battles in Vietnam. The U.S. had the reasons to enter Vietnam, but it was poorly executed. So in the end, the U.S. both lost and won the war.
South Vietnam was in danger of falling in 1965 just like South Korea was in 1950. From 65, when the first U.S. combat troops entered, to 73 when they left the South Vietnam was never in danger of falling to the VC or the North. The war between the U.S. and the North was ended with the Paris Peace Accord signed in 1973 which maintained the status quo of a North and South Vietnam with a DMZ like what North and South Korea has. Nixon pledged to aid the South again should it be attacked by the North but could not do this because of his resignation over watergate and also because the Democratic controlled congress ended any kind of Vietnam connected funding thus leaving South Vietnam hanging out to dry. For about a year after the 73 Peace Accord fighting in Vietnam had ceased. In 74 North Vietnam started gearing up for an attack on the South and eventually conquered the South in 75 which had no American military aid. Perhaps if we left a military force to protect the South then Vietnam would be like the Korean peninsula but congress voted against that and Vietnam was left to wither on the vine.
The US defeated the Vietnamese armies in the vast majority of times and only pulled out because it became politically untenable to stay in the war with the media almost opening supporting the Vietnamese. The media's goal of that was to blame Nixon even though Johnson started the war in 1965/1966.
With u.S,advisers and u.S.Airpower the south Vietnamese army dealt a crushing defeat to the north Vietnamese army in the 1972 easter offensive.Along with strategic bombing of Hanoi and the mining of the port of Haiphong the north was dealt a crushing blow that drove them to sign a peace agreement with the u.s. in January 1973.Noth Vietnam realized they could not win the war while the u.s. had even a small military presents and air power backing the south Vietnamese army.
Vietnam was never a decisive victory for the U.S. Since N. Vietnam took over & succeeded in their goal, they have the bragging rights. There are many slang terms that could describe the U.S. involvement in that war, i.e. snafu, fubar, etc. The U.S. even won a few key battles. But overall we lost that war -- in combat & politically. It was never "our war" to begin with. Maybe, that's the real issue? It was up to the people of Vietnam to fight it. The U.S. was in a support role that escalated into a mess. Iraq was very similar. The real question is: If the people of a nation are not willing to fight for it, why should anyone else get involved?
Here's how it went down.
US invades Vietnam to contain Communism (Allegedly)
1972 - troops still in Vietnam, North Vietnam crosses the 17th parallel to attack South Vietnam - Easter offensive - bad news for the US
1973 - the US pulls out
1975 - North Vietnam assaults South Vietnam, South Vietnam gives up
1976- Vietnam is united as Communist
So, the US slaughters 1 Millions plus Vietnam civilians, poisons the forests for generations, gives cancer to the following generations, the so-called "Good Guys" lose some 700,000 men and the "bad guys" lose a little more, say 800,000-1,000,000. Nothing is accomplished, and, actually, the mission is a failure, Vietnam becomes Commie anyway.
That sounds like a tremendous loss to me.
The Vietnamese people wanted the regime out, the regime got US to fight for them, but overall, the people won, the US and the regime were forced to flee for their lives, thus they lost. The people wanted the Chinese and the people supported them, body counts had nothing to do with it, though many of the bodies were not the Vietcong, but the locals that were supporting the Vietcong. This is what happens when the Holier than Thou Stupidity the US harbors has them fighting battles they should not have even joined, had they really done their homework. Same goes for the false weapons of mass destruction stupidity that shows how little homework the US does before this stupid Christian blunderbuss jumps in where it is no right to do so.
If the aim was to stop the growth of communism and prevent the north from taking over the south it would be unreasonable to claim anything other than the US of America lost the war. We shouldn't rationalize about having won more battles or having lost fewer men. US lost- period.