Considering Sandinista was recorded almost completely ad-hoc in the studio as a massive jam session, it is pretty impressive.
Anyway, he told me he once asked Strummer about the name "Sandinista," and Joe said it was just a word he'd heard in the news and thought it sounded really cool. He said he didn't even know what it was, he knew nothing about the politics of Nicaragua, and it literally could've meant anything. Only after it came out did all the leftist rock critics start assigning a lot of political meaning to it.
P.S. -- You should also hear Johnny Rotten laughing and ridiculing all the socialist rock critics who read so much into the Sex Pistols.