The problem with the emergency declaration is that, even if it’s technically legal (a matter of debate that will go up to the Supreme Court), it is clearly pretextual and a way to do an end run around the congressional spending power. The president himself in his press conference announcing the emergency said that he didn’t have to do it, but that he wanted to build new fencing more quickly than he could without the declaration.

If anyone shouldn’t be okay with this, it’s Congress. Under the National Emergencies Act, it can vote to disapprove of an emergency declaration by a president, who can, in turn, veto the disapproval (which Trump will do). A resolution of disapproval already passed the House, and seems likely to pass the Senate, the only question being how many Republicans will defy the president and vote for it…

One reason that Congress has ceded so much power to the executive branch and the courts over the decades is that it’s so often unwilling to take political responsibility and to protect its own prerogatives. Congressional Democrats didn’t utter a peep of disapproval when President Obama rewrote immigration law on his own, with not even a whisper of statutory warrant.