America only started their offensive after Russia started winning and likely only wanted to deny them Europe. And the heavy casualties in the war likely caused Russia to fold on the cold war as well, there were just not enough able men after the war to create families with about 80% of the male population in their prime dead. That low birth rate circle continues to date.
The world would've been a very different place with the USSR still in power and indoctrinating europes youth for generations.
America likely did save the Democratic western Europe at that time, just not from Germany.