If the president can, without consulting the courts or Congress, banish U.S. lawful permanent residents, then he can do anything. If there is no rule of law for some people, there is no rule of law for anyone. The reason the U.S. is a good place to do business is that, for the last 228 years, it has built a firm foundation on the rule of law. It almost undid that in a weekend. That’s bad for business.