Genuine question - can they really do this? Obviously if I, a not-even-millionaire, get a national security gag order, I'm going to follow it because I assume they'll bury me under the jail otherwise.
But the (b|tr)illionare class? I'd assume they have access to enough legal services to make even the government careful of trampling their first amendment rights. Is the national security gag order process so strong that the government doesn't have to worry about motivated, well-resourced actors buying really good lawyers and blowing up their favorite tool?