London paralyzed by Turkish invasion of Cyprus in 1974, Brexit in 2018

Forty-four years ago Turkish paratroopers landed in Cyprus. Soon afterwards a second Turkish invasion with armored units took place and Cyprus was cut in two. The French have a saying that nothing lasts longer than the provisional. It seemed obvious in 1974 that with the military dictatorship overthrown in Athens, and a reasonable non-military government in Ankara it should be possible to find a solution and restore the integrity of the whole island of Cyprus as a United Nations member-state.

Half a century later we are still waiting. In London, one of the guarantor powers in Cyprus, the British government, was paralyzed. Labour's Harold Wilson was in power but without a majority. He had to wait until a second general election in October 1974 to secure a tiny majority of just four members of Parliament.

The foreign secretary, James Callaghan, was a Euroskeptic with...