The US is the only country that ever developed nuclear weapons with the intention of using them. It was at the end of World War II, when tens of millions had already been killed, and moral restraints had largely been cast aside. But the US never used its nukes again, even when it still had a monopoly on them -- and all the other known nuclear powers got them in the name of deterrence.
The Soviet Union developed them to deter the US from launching a nuclear strike. Britain and France got them to deter the Soviet Union. China got them to deter all of the above. And Pakistan and India each developed them because they suspected the other country was working on them.
So why can't the rest of the world believe that North Korea is doing this in order to deter an American nuclear attack? North Koreans have lived 65 years with the knowledge that the US could do that whenever it wanted, and it is not maniacal to take out a little insurance against it.
The North Korean regime is brutally repressive and given to foaming at the mouth over minor slights. But since it has actually kept the peace for 64 years (while the US has fought three large wars and many small ones), it is hard to maintain that it is maniacally aggressive.
So why say it? Because if you don't characterise North Korea as insanely dangerous, then you cannot justify forbidding it to have ballistic missiles (which several dozen other countries have) and nuclear warheads (which nine countries have, and another four had briefly before giving them up).
Since none of the great powers want North Korea to have them, and they control the United Nations Security Council, they have managed to get special UN bans on both ballistic missiles and nuclear weapons for North Korea. Maintaining that the Pyongyang regime are maniacs is part of the programme, but it does frighten those who are not in on the joke.
It would be better if the ban worked, since the world has more than enough nuclear powers already. However, the ban is essentially unenforceable, and the heavens will not fall if North Korea does get a few nuclear-tipped ICBMs.
It will never have very many, and they will not be used for some lunatic "first strike" on countries that are tens of times more powerful. They will be for deterrence, only to be launched as an act of revenge from the grave. Like everybody else's.
What can President Trump do about this? He could try bribing North Korea into suspending its work on missiles and bombs. That worked once before, but not for long. There is really nothing useful to be done.
And what will he say about it? Nobody knows, probably including him.
�Gwynne Dyer is an independent journalist whose articles are published in 45 countries.
