Only 10% of the US is in a union. Who's going to lead it?

The biggest of those unions I'd guess would be AFL-CIO, which I suppose did a okay job leading the Minnesota strike

Roughly one in four Minnesota voters either participated in the January 23 day of shutdown and protest against ICE, or have a loved one who did...Of those participants, 38% percent stayed off the job, either because they did not go to work, or because their employer closed for the day of action... 45% of voters ​“generally support the call for no work, no school, no shopping as a form of protest.” https://inthesetimes.com/article/labor-general-strike-minnesotans-ice-protest-trump-cbp

Keep in mind those numbers are voters in minnesota, not super great for a bunch of "progressive" people.

Even the national strike on the 30th wasn't terrible, but neither had any economic effect. There just isn't enough organization, especially in key industries. People aren't educated on unions, even in communist circles a ton of us are running around without a clue what good union organizing looks like.