Here are some reasons why people believe those things.<p>First off, in the context of the Vietnam War, VC stands for Viet Cong.  I think that you mean North Vietnam, instead, because the Viet Cong were spent as a fighting force after the Tet Offensive.  Thereafter, the Vietnam War was mostly a fight between regular armies.<p>In 1969, Richard Nixon began a modest pull-out of US troops from Vietnam.<p>In 1972, North Vietnam <i>invaded</i> South Vietnam with 150,000 troops.  They had support from the Soviet Union in the form of tanks.  Lots of tanks.  Zhukov would&#x27;ve been proud of that force.  South Vietnam <i>defended</i> themselves with help from the United States in the form of air support.<p>Result: Fewer than 50,000 North Vietnamese soldiers made it back North.  American KIA: 650.<p>Perhaps not coincidentally, peace talks improved for a while before breaking down in mid-December 1972.  Nixon then ordered North Vietnamese cities to be bombed for eleven days (the &quot;Christmas Bombings&quot;).  Perhaps not coincidentally, peace talks resumed.  On January 27, 1973, both sides agreed to a cease fire, America would withdraw all of its forces, all POWs would be released, and South Vietnam would remain independent (<i>of the North</i>).  By the end of 1973, all US troops were gone.<p>Being a bunch of communists, the North Vietnamese lied about their end of the deal.  How&#x27;s that for fair and square?  They kept fighting to subjugate South Vietnam with the full support of the Soviet Union.  South Vietnam fought on with aid from the United States... until August 1974 (thanks, Congress!).<p>So, strictly speaking, America didn&#x27;t lose the Vietnam War in much the same way that tomato is a fruit and not a vegetable.  See?  History can be complicated.<p>As for &quot;doom predictions of the time,&quot; well, North Vietnam proceeded to aid communists elsewhere in Indo-China, just as the war hawks predicted (cf., Domino Theory: <a href="http:&#x2F;&#x2F;thevietnamwar.info&#x2F;domino-theory&#x2F;" rel="nofollow">http:&#x2F;&#x2F;thevietnamwar.info&#x2F;domino-theory&#x2F;</a> )  By 1975, Cambodia and Laos had fallen to communist insurgents.  In all of these places, they instituted revolutionary socialist reforms to overturn the legacy of foreign colonialist occupiers.  These reforms so impressed the locals that more than a million of them took to the high seas in hand-made boats in order to return to those self-same &quot;occupiers.&quot;<p>Here, in America, we have a number of Vietnamese neighborhoods made up of those people and their progeny.  The grey hairs among them would take issue with your evaluation of modern Vietnam as &quot;a functioning state.&quot;<p><a href="http:&#x2F;&#x2F;ngothelinh.tripod.com&#x2F;50_years_communist_crimes.html" rel="nofollow">http:&#x2F;&#x2F;ngothelinh.tripod.com&#x2F;50_years_communist_crimes.html</a>