Painfully long-winded (three hours and change), this docudrama about one of Japan's most notorious and violent political factions wouldn't be worth the attention if it wasn't for the fact that longtime director / agent provocateur Kōji Wakamatsu was at the helm. The movie itself, though, could have been directed by anybody. The first hour's a jumble of stock footage, uninvolving re-enactments and title cards, as the turbulent political world of student groups in 1960s Japan is laid out for us in numbing detail, and it leaves us with little sense that the film will matter for anyone who wasn't actually there.
The second hour is slightly more absorbing, as the United Red Army of the title starts as an earnest splinter group from another faction but gradually degenerates into paranoia and self-persecution with many of its own members murdered for being not ideologically pure enough. The only people we get to know well enough are the instigators of the purge; everyone else is just a name and a date of death.
The home stretch re-constructs the infamous "Asamasanso Siege" (as documented in Shocking Crimes of Postwar Japan). Here there are hints of the movie this could have been as the revolutionists barricade themselves in a mountain lodge, stand off against police for days on end, and face both physical and psychological warfare. But by that point the film has long since worn out its welcome. It's all good intentions for so little real payoff, one-and-a-half hours of movie in a three-hour bag. Then again, maybe Wakamatsu's point is that this revolutionary political stuff is supposed to be boring, but I'm dubious. Bonus points for Jim O'Rourke's mournful soundtrack, though.