Had the carriers been destroyed it would have been longer than a year, guaranteed. The US didn't have all of the resources for the battleships let alone the CV's.
Charon you are absolutely right, Roosevelt had too many investors in the German Reich. Henry Ford's picture was behind hitler's desk. Ford had given Hitler many trucks for military purposes. My grandfather despised FDR for all that he was worth until his death in May 1998. He was a Marine and fought at Guam, Okinawa and the cleaning up of China. FDR had split the Marines in half 3 Marine Divisions per Theater and my grandfather never forgave him for that.
Germany would never have captured Russia, it would have been the worst battle on record, IMO. The Intelligence Bureau headed by Sir William Stephenson was impressive. The whole Barbarossa offensive was delayed three months because of Tito and he "supposed uprising in Romania and the Balkans". This was all false info. that was being fed to the Reich's highest officials. Read "A Man Called intrepid" by Sir William Stephenson. He actually was prevented from writing this until 1973 so names would not be extruded from CIA operatives and in the British Spy Rings. This is one of the best books I have ever read having ANYTHING to do with WWII.
As long as Hitler was in charge they could only bully around the smaller countries, not Russia. this is my opinion. This is a fun topic to discuss and I hope this may come to the top of the list again.
Jay