President Trump wants $8 billion to build a wall on the southern border of the U.S. Congress refused to give it to him. So he declared a national emergency, in the hope that he can use his extraordinary powers to secure funding from other parts of the government.
A "national emergency" sounds like an extraordinary thing, but it turns out, it's really not. Liza Goitein is a co-director of the Liberty and National Security program at NYU law school's Brennan Center for Justice. She recently wrote an article for The Atlantic on national emergencies, and pointed out the U.S. was already in 31 formal national emergencies right now. Thirty-one! So we called her up and asked her to help us understand what a national emergency is.