@coldjoint,
You folks seem to forget that the House holds the purse strings. The House can suspend any program at all even if it doesn't make any sense. Nothing stopping the Speaker from suspending the housekeepers and food service personnel at the White House, they would never suspend Secret Service protection but they could furlough the people who plan the travel for Trumps extended family. In other words, Trump's family and friends would be free to use their own funds to hire commercial firms.
I still have nightmares about 'urgent' tasks from a HPSCI staffer coming in at 4 o'clock on a Fri demanding anything from how many desks are in your workspace to something more complicated. I have had to stay all night and call in other personnel in order to meet the 8 o'clock Monday morning deadline. You didn't dare not comply because they had the power to defund your entire mission.
Sadly, Trump doesn't understand that he can't simply threaten to sue, nor does he understand that the other branches of our government can twist his arm as well.