The Germans were doomed when they invaded Russia and declared war on the U.S. Our capacity to manufacture and innovate was just too great for the Axis. Which is why we could fight wars on two huge fronts and win. And if everything else failed, we had the atomic bomb.
Yep. And if there hadn't been a screw up at the Oak Ridge facility that caused the first batch of plutonium to be lost, that first bomb would have erased Berlin.
There has been a weird sort of fascination with the Germans in WW II and all of the strange but innovative dead ends they chased - 380mm siege guns, V-2 mostly unguided missiles, "Amerika bombers", even suicide planes. But the truth is that Americans and Brits ruled the technological roost from the get-go (with the Jewish refugees at the forefront). Our ships were better, our aircraft were better, our artillery was better, our radar was better and we had a working proximity fuze long before anyone else. Meanwhile the dimwit Nazis kept an 1898 bolt action rifle as their primary infantry weapon throughout the war. Guess it worked OK on unarmed civilians.
I have long believed that here is no more ferocious enemy to have than the United States of America. We take a while to spool up, but once we're there, kiss your tender parts goodbye.