Sacrificing a submarine or cargo ship isn't that big of a loss for delivering a strategic weapon.
Although the chances of successfully doing it while the US is on alert is low.
A sneak attack on the other hand would be much more successful.
If everyone gets nuclear weapons, there'll be no taboo.
But giving Japan nuclear weapons by 1941-ish is requires a POD that would remove the Pacific War as we know it from the timeline. It would need a Japan friendly with the West to import Uranium, as if I am not mistaken the only known deposits in the 1920's or 30's, maybe even the only reachable deposits with current tech where in the Belgian Congo. Even if you wank mining tech as well Japan would have no access to fissionable material except through trade, and in a world where everyone knows about nukes so early they would only be traded to a very friendly power.
Last edited: