chapotraphouse

Podcasts on US social movements... that's a tough one. You'll hear some episodes covering this on RevLeft Radio but because most socialist movements in the US are either quite small and fragmented or they haven't achieved a whole lot there often isn't a huge amount to cover.

For US actions against socialism, Blowback is really good, as others have already mentioned. Others are American Exception and some episodes of Guerilla History.

For theory, I strongly recommend Red Menace as well as a lot of the stuff produced by Socialism For All. There's also Marx Madness, We Read Theory, Red Book Club, Radical Reviewer (on YouTube), and a lot of the episodes of Teach Me Communism.

For current affairs, there's Citations Needed, Radio War Nerd (specifically about wars), Everybody Loves Communism, The Deprogram, and some of TrueAnon.

While this next recommendation doesn't fit any of your categories, I'd also recommend Actually Existing Socialism because they interview primarily academics on their areas of expertise in socialist movements and it's really underrated, although it can be a bit dry so it might not be to your tastes.

My overall recommendation would be to try out an episode or two of whatever podcasts take your fancy to see if you like the presentation style and if it's to your preferred depth. Some of these podcasts are more conversational and entry-level while some of them go much deeper and lean towards the more academic side. There no right or wrong in this matter, it's just about finding what suits your preference.