On March 16, as Crimeans voted in a referendum on joining Russia, a convoy of Russian minibuses and cars drew up to the center of Lytvynenkove, a village about 15 miles northeast of the peninsular capital. Members of the local self-defense committee of Crimean Tatars, the Muslim minority group who were exiled under Stalin but returned here when Communist rule collapsed, watched with trepidation as about 50 men, some in track suits and others in military uniform, got out of the vehicles. But the passengers hadn’t come to bully the local Tatar population, which had announced a boycott. Instead, they headed into the local polling station. The two white vans and the several cars were registered in Krasnodar, Russia. The men’s accents were Russian, and so from their appearance were they – those in uniform were Don Cossacks, a famed fighting force that served the czars and now, experts say, has become a sort of Pretorian guard for Russian President Vladimir Putin. “Political tourists” traveling by the van-load from one polling station to the next have been a feature of Ukrainian elections going back more than a decade – locals call it “carousel voting” – but this was the first time that anyone had heard of foreigners getting into the act, a Tatar organizer said.