Draining the swamp also includes the judiciary. These liberal judges are lagging legacy of the Obama administration.
We all knew this would not be easy. Frankly, I did not expect this EO to be challenged successfully, since the law and judicial precedent is pretty clear on the presidents authority to do this. Just like Obama did.
In the end the EO will stand.
Maybe that's why Trump took this route. It's as if, "Okay, you want to play hardball, lets fight this all the way to the Supreme Court. I want to teach you commie judicial judges who's boss right off the bat. I'm not putting up with this crap for eight years."