There’s another option. The US making another country so fearful of regime change or destruction that they fire first. And the US has repeatedly attempted and accomplished regime change, several times resulting in the death of the former leader of the country.
Also, yes. The US would fire first if it were losing a conventional war, which of course would be unlikely in the next few decades. We’ve already seen that the US did use nukes to avoid losses invading the Japanese mainland.
The idea that the US would use nuclear weapons in response to losing a conventional war is not well founded. One would not necessarily consider Vietnam nor Afghanistan as conventional wars, but they were lost, and nuclear strike did not happen.
I don't really see any likelihood for the US using nuclear weapons in a _deliberate_ first strike outside of parts of the continental US being invaded and occupied.
The US wasn’t being invaded and didn’t need to continue the war to prevent a future invasion in those cases. Whereas Japan would’ve continued the war and brought it back to the US mainland eventually.
This is simply ahistoric.
Japan was on the brink of loss and everyone knew it (including all of Japan's military and political leaders) -- Japan was already suing for peace long before the bombs were dropped. The main sticking point was the conditions of surrender and the Japanese were deluded (partially by the US, intentionally or not) into thinking Russia could get them more favourable surrender conditions. These delays, combined with the use of the bomb being a foregone conclusion in the minds of the US leadership regardless of Japan's stance and what seems to be at least some wish to show America's might, lead to the bombings.
No reputable historian (nor the statements made by several important military figures at the time) could make a credible argument that in 1945, Japan's loss was not already a foregone conclusion irrespective of the bomb, let alone suggesting that Japan would be able to even attempt to invade the US. If the US had explicitly stated they would not try the royal family for war crimes and keep the 帝 (emperor) alive, Japan would've surrendered (this is literally the only important condition they wanted, and it's what the US was planning on doing anyway).
If you'd like to watch a very long video explaining the events leading up to the bombings with a very detailed timeline: https://youtu.be/RCRTgtpC-Go
And yet many senior political figures in the US repeatedly call for regime change, coup, uprising, and worse. Why do those things?
... to happen in the US, and nobody nukes them either.
Clinton made that type of proclamation when he was in office, and the conservatives went nuts about it. It's really the only way to not escalate to total global devastation.
nukes <> conventional weapons