Make the USA nearly undisputed in the 20th and 21st century.

What could be done to make American power in 1900-2017 be overwhelming?

Here are some instances I can think of:
World War II absolutely cripples Germany and the Soviet Union, but still ends in an allied victory

US wins Korea and Vietnam.
Devastating Sino-Soviet War, as well as a larger Indo-Pakistani War
US bases in the Philippines stay.
 
Hmmm...I think a good starting point would be The Communists losing the Chinese Civil War. No PR means you havea unified Korea and vastly-lessened Soviet power.
 
Americans are distinctly underwhelming 1900-1917, OTL minor expeditionary forces around the Caribbean notwithstanding. Definitely a sleeping giant pre their WWI entry. Possibly a third term for Roosevelt and earlier naval build up might help? Otherwise settle for 1917- 2017.
As stated above, Communist defeat in China would weaken the USSR and leave the USA relatively stronger, as would avoiding WW2 and Nazism(Britain, France, Germany and Italy more or less cancel each other out and keep USSR out of Eastern Europe.
No rise of Communism and a fairly weak and disorganised Russian Republic might also assist.
 
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