This came up in another thread and I am surprised it is not as well known: General strikes are illegal in the United States since 1947’s Taft-Hartley Act.

https://en.m.wikipedia.org/wiki/Taft–Hartley_Act

Attempts to organize and exert political and economic influence have to do so under the parameters of that act. Unions can’t support these things openly or officially without violating the act. So these things have to be called something other than a general strike to avoid persecution. They’re essentislly stripped of major legitimizing and organizing organ: labor unions, by default.