Dixie...so...according to you, because we lost and didn't stick around a few more years and "win", we somehow failed to stop the spread of communism.
Not what I am saying. Our withdrawal from Vietnam dealt a serious blow to American credibility on the world stage. Our enemies knew, from that point forward, we did not have the will to fight a protracted war of attrition, that we would fold if the risk were too great. Our allies realized that we would not stand with them against Communist aggression, and thus, made them more susceptible to negotiating with Communists for their future. Pol Pot and the Killing Fields in Cambodia, I believe, were a direct result of our withdrawal from Vietnam. Millions were slaughtered... but I guess they didn't mean anything to you, since they weren't Americans.
There is simply no way to know what might have been, had we won Vietnam... Perhaps Cuba would have fallen as well, maybe the Cold War would have ended sooner, or we could have possibly had to deal with the threat of Islamofascism in 1980, instead of 2001. It's impossible to try and discern what might have happened, but one thing is for certain, those who gave their lives for the cause, would have been justly honored for their sacrifice. Vietnam would have been remembered as a victory for America, not a disgrace.