Why Trump's threat to declare a national emergency freaks out Republicans

The danger to congressional Republicans isn’t having to overcome a presidential veto, but in having to vote on the resolution itself. Any such measure would be considered privileged — if, for example, the House passed it then the Senate would be required by law to vote on the measure within 18 days. Senate Majority Leader Mitch McConnell would be powerless to stop a floor vote.

Republicans have been looking for a way to avoid that altogether. For weeks, GOP leaders in the Senate have publicly tried to dissuade Trump from declaring a national emergency. Last month, even before the end of the 35-day government shutdown, one GOP senator approached the White House counsel’s office to encourage the President to embrace a narrower executive action to fund a border wall without declaring a national emergency, according to a person familiar with the conversation. That would limit Democrats’ ability to block Trump’s actions, and also the amount of federal dollars he could use to start building the wall.

That’s why, for all the public and private appeals about not pursuing a national emergency declaration, Republicans still worry Trump won’t be satisfied by anything less. “You just never know what direction this White House will go,” says a Republican Hill source.