In the event of a war breaking out over Eastern Europe, the first thing the Allies would do is pardon and re-equip any Germans who wanted to help turn back the Russian invasion. They would get a fair number of experienced officers and men that way. Even though the German manpower pool was at least as drained as the Russian, it would be a significant boost to immediate combat power.
To start that sort of war you'd really need Stalin to launch an offensive against the West. Anything smaller, like one US general causing a 'shots fired' incident, would be squashed and resolved diplomatically. The US was focused on the Pacific and everyone else in the Allied camp focused on peace and reconstruction; there was a recognition that handing over Eastern Europe to the Russians was not ideal but no appetite to continue combat operations and take millions of more casualties over it.
The Allies greatest problem was supply, especially petroleum products. The Soviet's greatest problem was also getting supplies forward to their troops, but those men are more accustomed to doing without than their Western counterparts. With whatever remains of the armies of Germany, Italy and the minor eastern nations switching over to the Allied side (an assumption not perhaps founded on fact) I think the Allies could blunt or just withdraw before a Soviet offensive, wait for it to reach its stop line and then grind it down and throw it back. Since no-one is really ready for another all-out war in Europe, the diplomats would get busy, secure some concessions in each direction and hang whoever started it and/or was convenient.
Don't forget it wasn't just Patton but Churchill who explored the possibility of going after the Soviets, to the same conclusion: no way to get anything of strategic value and not much way to achieve success without massive casualties, and a serious risk of defeat.
Just my opinion here:
Patton was an officer of the old-Army type, born and raised in the South and coming from a military family. While his interests included horses and shooting, they also included books, military history and biography, and modern armored warfare. His public persona was 'carefree, confident, hell-for-leather, blunt and bluff' but the man was not ignorant. He foresaw the possibility of a German counter-offensive in the winter of 1944 and had his staff prepare contingency plans, which other generals like Eisenhower did not. I would not describe him as an intellectual, but his letters to his wife contain many references to the books he was reading or had read. So - a bit narrow in focus, perhaps, but not unintelligent.
The great preoccupation for Allied corps and army-level generals on the Western Front was how to get to Berlin first, or at least ahead of the Russians. That was the driving force behind Montgomery's 'Market-Garden' fiasco and a central concern for Patton, whose plans were denied. Added to the luster of being the first into the enemy capital (remember the pull of Rome on Allied strategy after Salerno, and its effects on Anzio) would be the professional pride of getting there ahead of the Russians. From that it is a short leap to think about planning for contingencies... the US had prepared plans for war with Britain; I'm sure the man who saw the 'Battle of the Bulge' coming would have thought about what his troops should do if attacked.
It would be obvious to anyone in 1944-45 that the only two powers left standing who had a substantial military economy and who could field a sizable army were the US and the USSR - Britain was exhausted, France, Germany and Italy in ruins and Japan shortly to go under. And it would be entirely in character for an officer like Patton, who relished leading men in combat, to propose extending the current war to the biggest opponent available. But any serious attempt by him to start a new, intramural war would have been stopped by his subordinates, scuttled by his superiors (Bradley and Eisenhower), unsupported by Montgomery and Britain, and stamped out by the diplomats.
So... was Patton ignorant? No. An old-school officer of the American-Southern-Junker type, perhaps, interested in riding and shooting and women. Brash and blunt and swaggering in public, more sensitive in private (as shown by his letters to his wife). Well-read in military matters, a gifted strategic thinker and a good combat leader. Narrow, not stupid; enjoying being a general of a mighty army on a great crusade but no fool; engaging in a bit of rough talk - 'that guy over there, think I could take him? What about that guy' - but not crazy. Strategic minded - 'one of us will run the world after this is over; us or the Russians?' - but not rash enough to go against his orders and start something on his own.
George Marshall looked for officers who were cheerful, confident and competent - in other words, men who could deal with whatever situation they found without complaint, lead their troops confidently and deliver results. Patton, despite his breakdown mid-war (which the Army was willing to treat and ignore until a reporter made it front-page news) was one of those.
Baseball player Ernie Banks once said, 'Hey fellows - it's a nice day; let's play two!' George Patton was in his element at a great moment in history; he knew it wans't going to happen but he couldn't resist saying, 'Let's play two!'
