"All a mess. And a very scary mess. I was watching a TV programme about the Great War, and how a seemingly peripheral terrorist assassination built up over a few weeks into an unstoppable rush into total war. And then turned over to the news..."

I think you are looking at the wrong war.

Think rather of the Sudetenland and its annexation at the point of a gun "to protect German speaking citizens", which escalated into the conquest of Czechoslovakia by the Nazis.

A much closer parallel to Putin's referendum at gunpoint. Who's going to argue with a bunch of masked men with Kalashnikovs?