I doubt any remotely rational actor would look at things that way. Nuclear weapons are more potent than they were in WWII and more numerous. And also more deadl

I doubt any remotely rational actor would look at things that way. Nuclear weapons are more potent than they were in WWII and more numerous. And also more deadly, due to increased population density in most urban areas. If the same nuclear bombs were dropped in the same locations today as in WWII nearly ten times as many people would die. Moreover, the economic loss would be extreme, which serves as a further deterrent.