Emergency powers are no blank check for building a wall

On Friday, President Trump said that he wouldn’t rule out declaring a national emergency to justify building his border wall. Speaking from the Rose Garden, he told reporters, “We could call a national emergency because of the security of our country, absolutely.” He added: “We can do it. I haven’t done it, I may do it. I may do it. But we can call a national emergency and build it very quickly.”

In theory, that sounds like a good way to circumvent a troublesome Congress. In practice, declaring a crisis to fulfill a campaign promise is a terrible and probably illegal way to govern.