First of all since Japan was in the middle of invading China and murdering and raping millions of Chinese in Manchuria while the Russians were doing jack $hit to fight Japan and Stalin had a non aggression pact with Japan so I highly doubt the Chinese would have allied with the Soviet Union. In fact the Soviet Union waited to officially declare war on Japan until August 8, 1945 - 2 days after the first atomic bomb was dropped on Hiroshima. This alone negates your argument.
Also in 1945 between the US Army and Navy America had 70,000 aircraft to the Soviet Unions 18,500. Furthermore the Soviet Union has nowhere near the aircraft manufacturing capability of the US. (source: https://airpower.airforce.gov.au/APDC/media/PDF-Files/Pathfinder/PF119-Worlds-Fourth-Largest-Air-Force.pdf)
Also in August of 1945 we had a Navy that dwarfed that of the Soviet Union:
BATTLESHIPS 23
CARRIERS, FLEET 28
CARRIERS, ESCORT 71
CRUISERS 72
DESTROYERS 377
FRIGATES 361
SUBMARINES 232
MINE WARFARE 586
PATROL 1204 119
AMPHIBIOUS 2547 275
AUXILIARY 1267 406
SURFACE WARSHIPS 833
TOTAL ACTIVE 6768
America would have easily blockaded the Soviet Union and Japan, wiped out whatever navy the Soviet Union had, and the US Army Air Corp and US Navy carrier aircraft would have eventually chewed up Soviet tanks and artillery without needing assistance from the UK, Canada, Australia, or France.
What part of we were bankrupt don’t you comprehend. The bucket was empty. There were no more resources. Hardly any more people.
You seem to think the US was full of flag waving patriots willing to do anything. While that might have been true in 1944, the letters I read from 1945 were anything but enthusiastic.
Starving out Japan would have taken years and millions of lives. It wasn’t necessary.
Starving out Russia would not have happened.
China would have ended up ruling the world.