If you don't hire them the Biden administration will come after you, like they did with Elon Musk, who was trying to OBEY the law by hiring US Citizens. People will probably say that it doesn't matter for NASA work, however, there is a lot of dual use of people for civilian and DoD/IC work, so employers try to hire people who can at least get a clearance. Of course that doesn't matter now since PEDOTUS would not even qualify for ANY clearance level since it's documented that he is compromised by accepting bribes from the CCP (and other foreign entities) via Hunter.