Explanation: During the US Civil War, various interests came together in defense of the Union against the attempt of the Confederacy to enshrine slavery in perpetuity. Strange though it may seem, two of the staunchest supporters of the Republican Party (and the Union) of the time were labor radicals (such as the exiles from the European socialist revolutions of 1848) and wealthy industrialists - it was really the big-tent “Fuck off slavery” party. Lincoln himself was called a “single-minded son of the working class” by Karl Marx, and while there’s a bit more adulation than precision there, well, as Lincoln himself once said…

“I know one thing- there is a strike! And I am glad to know that there is a system of labor where the laborer can strike if he wants to! I would to God that such a system prevailed all over the world.”

And now only the state can do it. Thank you 13th amendment.