Probably Alaska.
These were built to attack Germany from the mainland US, designed when it was not a sure thing that England would stay free:
“... Japan gets nuked more than twice in 1948 ... “
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And where would those bombers have taken off from?
You are assuming that we would have gone island hopping like we did in the early forties so as to make a slow approach to the Japanese islands in order to secure Pacific bases.
And what about Europe? No way that we could’ve maintained the lend-lease program, all of Europe would have fallen to the nazis, no shipping to Murmansk to help the Russkies, nazis riding roughshod all the way to the Urals and beyond, Britain defeated, mid-east oil in nazi hands, etc. etc., no D-Day.
In His mercy the Good Lord gave us Admiral Fletcher (The American Lord Nelson) and good and lucky decision making at Midway.
How else to attack the Japanese Empire in the 1940s?
By August 1945 the American war machine was just getting “warmed up”. There were 15 long-hull Essex class CVs, 2 Iowa class BBs and 5 Montana class BBs planned. In early 1946 the production of atomic bombs was ramped up to 3 a month.
“And where would those bombers have taken off from?”
Where did Doolittle’s raid, which was prior to Midway, take off from? The Japanese homeland was within reach even without island hopping. Maybe not reliably, and maybe those in charge would be reluctant to risk so expensive a thing as a nuke on a suicide mission. But it was possible, and unlike with conventional bombing runs it only takes one plane and one hit.
Probably Alaska.
These were built to attack Germany from the mainland US, designed when it was not a sure thing that England would stay free:
B36 from CONUS
Fletcher’s downfall was his somewhat unfairly perceived timidity in the Solomons a few months later. I say unfairly, because he had to safeguard the remaining carrier a bit.