China's Communist conquest was a war of the scale of Vietnam. The Communist takeover of China involved several times more deaths than the entire Vietnam war. Ultimately tens of millions of people in China died in conflict and famine over three decades as Mao established control of the country.

Neither world war had singular causes, they were diverse and complex, involving dozens of nations over long periods of time. That's particularly true of their origins.

The Vietnam War wasn't started by either the US or European powers. It was a civil war, in which the Communist North was attempting to conquer the South, as North Korea attempted to conquer South Korea, and Communist China conquered the Republic of China. The Vietnam War also was not finished or continued by the US; after the Paris Peace Accords, and after the US left, the North predictably proceeded to continue its prior military conquest of the South.

Middle Eastern wars haven't stopped for the last two thousand years. Who are you planning to blame that on? Who would be the non-guilty parties? China currently gets an immense amount of its oil from Middle East theocracies.