I just wish a show would put the Vietnam War into some perspective, starting with the Soviets starting a civil war in Greece in 1946 as a means of taking control of the country. That went on until the Soviets realized we weren't going to let them have Greece and they started messing with Germany by starting the blockade of Berlin in 1948. When that failed, the Soviets realized we weren't going to let them take control of anyplace in Europe which forced them to change their strategy.
Enter the invasion of South Korea in 1950. The Soviets didn't take over South Korea, but they didn't lose their satellite state in North Korea, which was a step up from their previous efforts. Enter Vietnam in 1955.
There is much made of US losses from 1955 to 1975. 58,000+ dead, 153,000+ wounded, 1,600+ MIA, but not so much is made of the Soviet losses. The Soviets "won" in Vietnam, but it was a Pyrrhic victory. The Soviets spent billions in hard currency to support the North Vietnamese, but aside from bragging rights they got nothing for it but a dirt poor country with few natural resources and lots and lots of needs. While little has been let out of what impact this had on Soviet thinking, we can judge the effect based on what the Soviets did next, which was the same thing they did when they realized Europe was a loser for them... they shifted their thinking.
Enter Nicaragua and Central America. The impact of the Vietnam War on the Soviets was it's not worth spending billions to get nothing, so they decided to make more of a move in America's back yard so they could at least say they were intimidating us the way we were intimidating them in their backyard. We countered them there, and between the costs of Vietnam and Central America, the Soviets became so broke they had to make a move on the Middle East to get their oil but needed Afghanistan as a way point, and we all know how that ended up.
So, with all that in mind, one must ask what would have happened if we hadn't fought in Vietnam? First, the Soviets would have taken control of Vietnam quickly, followed by Laos, Cambodia, and later all of Korea. What would have been their next logical target after easy wins throughout South East Asia? Japan and/or Australia, and invasions there would have certainly led to WWIII, which means no one reading these words would likely be alive today.
So I wish people would focus as much on what likely would have happened if we hadn't sacrificed then as they do on what happened.