Pardon my ignorace, but what is the UPCA?
United Provinces of Central America; some people call them the USCA instead; also a revived UPCA would probably end up being a good deal for the US (Nicaragua canal, for one), while butterflying away the independence of Panama for similar reasons.
It did, but the idea kept re-appearing, and nearly succeded a few times after that. IIRC, the latest proposal that got close before being derailed was in the early 1920s.Oh, that old concept? I thought it broke up in the 1840's.