George C. Marshall
Man landing on the moon. The restoration of relations with mainland China The withdrawal of US troops from Vietnam
Certainly Japan could not have made a massive withdrawal of troops they had in China and Manchuria late in 1944. But they did have close to two million troops. At least 500,000 battle tested troops could have been sent eastward to defend Japanese held islands against the steady advance of the US's island hoping troops. They failed to do this, reasons are unknown.
Vietnamisation
South Korea to settle the republic of Korea
1,000
the u.s send troops into Cambodia. apex
No. China is kind of afrenemy to the U.S. and definitely wouldn't American troops within its borders.
Taiwan
the u.s send troops into Cambodia. apex
Boxer rebellion
Nationalist China was an ally but did not send troops. The others were neutral.
the U.S had 500 troops already stationed in japan