Whatever else might be said about Donald Trump, the fact is that he has provided a valuable service in producing a national and international discussion of NATO, the old Cold War organization whose mission was to protect Western Europe from an attack from the Soviet Union, which had been America's partner and ally during World War II.

The obvious question arises: Given that NATO was a Cold War institution, why didn't it go out of existence when the Cold War ended, as its counterpart, the Warsaw Pact, did? Indeed, let's not forget that that's precisely what U.S. officials assured Soviet officials would happen as the Cold War was ending. Shut down the Warsaw Pact and we'll shut down NATO.

But U.S. officials double-crossed the Russians. Even though the Warsaw Pact, which consisted of the Soviet Union and Eastern European countries, dismantled, NATO didn't.