Britain is America’s closest, most historically reliable ally. And it desperately needs President Trump’s help. The European Union is refusing to yield on a key Brexit issue, the so-called Irish backstop. And this is preventing Britain from getting Brexit out of Parliament.

More on that in a moment, but first, let me explain how Trump might pressure the EU. The president could address EU leaders, perhaps via Twitter, and say, “If the EU doesn’t want to work with Britain on the Irish backstop, that’s fine. But in that case, the EU can forget about a U.S. trade deal, forget about U.S. acquiescence on tariffs threats, forget about continued military basing in Germany, Italy, and Spain (we can move to pro-British/pro-American Poland), forget about U.S. private investment facilitation, and forget about the continued provision of boutique U.S. intelligence capabilities” (which have saved hundreds of European lives over the past five years).