Just because the USA came second best, it doesn't mean they are losers. They were at least better than Mexico or Bhutan or any other country that didn't participate.
You may say that they should be labeled as losers because they failed miserably to meet their stated goals despite having the strongest and best equipped military force in the world fighting a bunch of miserable peasants with no access to advanced technology, but hey, at least they were brave enough to venture into unknown jungles in Southeast Asia filled with enemies, isn't that a victory already? Don't you think they also deserve a trophy?
Besides have you stopped to think about what is the consequences of labeling people losers? They will eventually develop a low self esteem and an inferiority complex. If people start ridicule the USA as being unfit to win, they may never want to participate in wars again.
Despite popular opinion to the contrary, the US won nearly ever major battle in the war (except for the Tet offensive ... And only briefly). US casualties were around 55,000 soldiers (second deadliest war), while the Vietmanese lost somewhere around 2 million (between 30% and 50% civilians). The only reason we withdrew despite are victories was bad policy making, growing hatred for the war (mostly due to the draft), the fact that the US doesn't like any war that goes longer than 4 years.
It's too obvious! We won in every way possible! As you can tell in the picture for this post we have about 5 helicopters covering the entire land, and no enemies to be seen for miles! America has reached total domination! Even our people on the ground are alive!
And You're Welcome.
Eventually, North Vietnam just invaded South Vietnam anyway and the entire country became communist. America did not intervene that time. This suggests that Nixon simply gave up on the Vietnam war and offered them peace with very few terms of agreement which America could actually enforce. They simply couldn't win a guerrilla war.
We didn't save South Vietnam from communism, and we even had a role in Pol Pot's rise to power in Cambodia (though the NVA also had a part in that). If that isn't enough we ended up strengthening communism's presence in the region as the we basically gave them all the propaganda they would need.