A tragic example of how a matter of a few inches (in the placement of the bomb) left Hitler alive and in power, kept the war going and consequently, led to the deaths of easily over a million more soldiers, POWS, civilians and concentration camp inmates.
But for a nail...
The real tragedy was that the Allies accepted the armistice that put WWI on hold until Hitler (in conjunction with the USSR) broke it by invading Poland. WWII was just Round 2 of WWI (with some differences in the side players). If the allies had refused the armistice (asking a lot, after the carnage they had already suffered prior to 11/11/1918) they coulda, woulda, shoulda permanently prevented WWII.But once the WWI armistice was entered and broken, the only politic approach (in America) was FDR’s demand for unconditional surrender (a promise that “We’re not going down that road again"). People wonder why the Germans fought WWII to the bitter end; “Unconditional Surrender” was why. As well as the fact that the Nazis had seen to it that an enormous fraction of the German military had guilt over - at a minimum, had good reason to know about - mass murder and war crimes.
Those considerations aside, it would have made sense for the Anglo part of the Allies to agree to a separate peace with Germany which would have kept the USSR out of the Balkans and Poland. But those considerations prevailed. And besides, FDR himself was enough of a socialist to want the USSR to work out.
Stalin would have liked the Normandy invasion to turn into a meat grinder that left him free to go all the way to Paris. In that sense Hitler’s Battle of the Bulge - consisting as it did of a major diversion of troops from “der Ostfront” to a westward offensive against American, British, and Canadian forces - must have suited Stalin. And would have suited him perfectly if it had succeeded.