America might have lost the fight in Vietnam, but as this 2014 poll from Pew shows, capitalism won the war:
Note the actual question asked, which is the right one: are people better off in a free-market economy given the wide disparities in wealth that might result?
Vietnam's results are almost comically lopsided: 95 percent are for the free market, and only 3 percent are against it. They're so lopsided that it almost makes you question the data, though given the quality of Pew's work and its experience with international polling, I trust it. But even China's results slightly edge out the United States: only 18 percent of Chinese doubt the free market is better, while 25 percent of Americans do.
When you look deeper into Pew's numbers, China and Vietnam are outliers in another way, too: they have an almost unique combination of economic growth mixed with incredible optimism about the future. Residents of Vietnam, for instance, see a much brighter future for their children than residents of Nigeria, Peru, or India, despite the fact that all three countries have seen more growth in recent years than Vietnam:
Pew also asked about the best ways to solve inequality, and found that emerging economies were likelier to favor low taxes on the rich and on corporations than poorer nations:
Pluralities or majorities in 22 of the 44 countries surveyed say to reduce inequality it is more effective to have low taxes on the wealthy and corporations to encourage investment and economic growth rather than high taxes on the wealthy and corporations to fund programs that help the poor. Publics in 13 countries prefer the high tax option.
Overall, advanced economies (median of 48%) are somewhat more supportive than either developing (40%) or emerging (31%) countries of using high taxes on the wealthy and corporations to address income inequality.
(Poll via Conrad Hackett.)