The Whole History Of The World Could've Been Changed If A Jewish Mobster Killed A High Ranking Nazi Just Before WWII

There's a Youtube channel that pops up on my algorithm sometimes called "Alternate History". Honestly, I am not even really sure that is the correct name, but basically it goes through a historical event and maps out what the world would've looked like if things had occurred the other way. What if the South won the Civil War? What if Kennedy survived the assassination in Dallas? What if Rome never fell? What if the Nazis didn't invade Russia? Interesting bit of history fan fiction. 

I want to write my own version of events surrounding Bugsy Siegel. Almost like "Inglorious Basterds" where they killed Hitler and all high ranking officials in the Third Reich. Siegel was almost a Basterd by mistake. The story goes that he went over to Italy prior to the United States' involvement in WWII and tried to sell an explosive called atomite to Mussolini. Mussolini passed him on to Hermann Goring who was head of the German Luftwaffe. Siegel fucking HATED Goring. Siegel was a jew. Goring obviously was a Nazi. Naturally they weren't going to get along. Apparently it was deeper than that though. Siegel sat in that meeting just fantasizing about shooting Goring right in the face. Allegedly he had to be talked out of killing Goring on the spot and he eventually left the meeting without incident. 

Imagine if Siegel wasn't talked out of it. Imagine if he had pulled the trigger and murdered Goring. That meeting happened in 1939. Before Pearl Harbor and also before Hitler decided to invade Russia. What happens if an American, Siegel, assassinates one of the highest ranking officials in the Reich? Does Germany see that as an act of war? Does Hitler declare war on the United States? Does the US involvement in Western Europe earlier force Hitler to throw Operation Barbarossa in the drawer and divert all the resources he used against Russia to defeat UK and USA? 

You'd have to think that without being forced to fight brutal wars on two fronts, the Germans would've been able to hold off or perhaps even conquer the British Isles and at least play America to a stalemate. What does that mean for Europe? Does Europe become a permanent Nazi sphere/empire? Hitler always hated the communists, so maybe he turns on them after reaching a conclusion to a War with the West. Maybe the balance of the 20th century is a trilateral Cold War. Maybe Hitler develops the atomic bomb first and uses it to destroy enemies of the Reich all over the world. 

It's a crazy thing to think about. One gangster, one bullet, and we are living in a completely different world today.