Except it wouldn't be 75k workers, it would more along the lines of 30k, maybe 40k if they really amp up the organization. The government would have the option to fire every single one of them, as long as they could prove the individual was participating as part of an organized walk out/slow down/stoppage. There are many people that would ignore such pleas/organization - much more than I think the people calling for a "strike/work stoppage" realize. There is ample precedent for the firing of those individuals that take part, and I do not get the sense that the sitting administration is in any mood to tolerate such an event very well. There are temporary options available to the Executive branch, and I am not so certain that a strike will bode well for the Union in a legal sense (if they are a part of the organizing and or striking).