The U.S. has been scrambling to hire more air traffic controllers for years. The longest-ever federal government shutdown might have made that even harder. "We need more of them to come into the profession, and this shutdown is going to make that more difficult for us to accomplish that goal," Transportation Secretary Sean Duffy said at a press conference at Chicago O'Hare International Airport on Tuesday, a day before Congress signed a bill to fund the federal government through January,