The homeland? Yikes.

The last time there was an attack within the United States’ borders it notably ended with a self-owning combination of perhaps the largest bureaucratic waste of time and money in human history (DHS/TSA) and the systematic erosion of enumerated rights.

Dropping nuclear bombs on Japan was in an entirely different context which has no relevance here. We're not in the middle of a global war (nor is anyone even at war with Mexico), nor in a nuclear arms race asserting nuclear capabilities for the first time in history.

You're forgetting all the times the US failed too, and those cases weren't even on its own border. Iraq, Afghanistan, Vietnam... the list is very long. Creating an existential threat on your own border is a bad move for anyone. Remember how bad Columbia got? I guess not. The current situation has the potential to be much more dangerous.