Do you have a problem with this?
One of the most impressive things about WWII to me is how big and strong the military industrial complex got in the U.S. During the war. One of my history profs at State said that if the war had not ended, the U.S. Was on pace to make more airplanes than we could park, including battle losses. Same for tanks. And with the new declassified info, an nuke every 2 weeks indefinitely. That's crazy.
Sort of sounds like it.
We were building war implements for, mostly England, prior to us entering the war. Check out the Lend Lease Program.
So when we were drawn into the war, some of our capabilities were already in hand, ready to go.
Without the US manufacturing capability, and protection due to Ocean separation, things might have been much different.