You're right; there are limits to that excuse.

In the case of North Korea, my excuse is "I haven't put the time into it because it's a small country on the other end of the earth -- nuclear armed, but without effective delivery devices and massively outgunned. I wasn't prepared to give a lot more detail in the context of an interview that isn't about geopolitics. If you want me to research I can."

Look, that’s better than pretending there’s nothing wrong with North Korea, because you wasn’t there personally and hence cannot talk of the matter.