Americans lost something like 400,000 soldiers on all fronts combined. UK lost less than that. Military-wise, they were both on sidelines of the war in Europe throughout much of the war. Three out of four dead German soldiers were killed by Soviets. Americans fought a few battles here and there, but they were nowhere near as powerful or experienced as Soviets.
I will admit that the U.S. had superior navy and possibly air force. Soviets got all their territory back by the end of 1944 and their industrial capacity was restored. UK and France were in ruins, United States had extensive military industry but limited capability to bring their new tanks and cannons across the Atlantic.
At the V-E Day, United States had enough fissile material for three nukes and no capability to produce more in the near term. Three nukes wouldn’t have made much difference against Soviet-controlled Eurasia.
