LONDON - At first sight, the election of a new president in Slovakia should command little attention. The central European country is relatively small: by the size of its economy, it is ranked 18th out of the European Union’s 27 member states. And the position of the Slovak president is mainly ceremonial: real power rests with the country’s prime minister.

Still, the election of 48-year-old Peter Pellegrini as Slovakia’s new president has sent shock waves throughout Europe. For it is seen as yet another victory for populists of either the far-left or far-right variety, who reject the continent’s mainstream political parties and threaten to shatter Europe’s consensus in backing Ukraine’s fight with Russia.