> Russia has 12, mostly in former Soviet countries. China has 3

To be fair, you're comparing land powers–that tend to annex their holdings–with a maritime power, who tend to trade with and maintain favourable ports at their conquests/allies. So yeah, China doesn't have any foreign bases in Tibet. But that's because it annexed it in the 1950s.

Put together, America obviously has a larger military than China or Russia. But before Russia became a rump, the Soviet Union could marshall military resources comparable to–and for one decade, in excess of–those of the United States for much of the post-War era.