It wasn’t long ago that Havana’s Plaza of the Revolution was packed with American tourists knocking into each other with selfie sticks while taking photos of the iconic image of the revolutionary Che Guevara and trying to catch a ride in a candy-apple red 1952 Chevrolet Bel-Air. Today, those polished 1950s-era American convertibles that came to symbolize quintessential Cuba sit empty, the tourists they once carried largely gone. The drivers spend their lives like most Cubans do: coping...