A reader reminds me of the Japanese nuke program:
Derb—Disagree with your assertion. The U.S. was aware as of May 1945 that Japan was moving ahead aggressively with its own atomic weapons program, and had been sharing material and information with Germany.
Therefore, it was a potential threat to the territorial integrity of the United States – one nuclear equipped kamakazi submarine in New York harbor would have demonstrated that most expeditiously.