Binnie, Patton was one of the first guys who predicted the Cold War. His idea was to hit the Soviets at full-force since they're fatigued from the war, their troops in disarray and most of their reinforcements depleted or concentrated.
The US command basically told him no It's still up for debate but I believe the US would have beaten the Soviets even without the A-bombs, but there would have probably been MANY victims on both sides, plus most people were getting tired of the war.

Short answer: America didn't want another war; they wanted it to end ASAP.
He was stopped because the Russians had wanted Berlin and probably hinted that they would have fought even the Americans for it. The war was much more "personal" for the Russians who suffered A LOT more casualties than the US, UK and the rest of Europe combined.