MARKED by biting winds, icy roads and a cruelly unenthusiastic sun, January, Charlemagne dares to venture, is not the best time to visit Latvia. But this year it is not a bad time to be Latvian, for the small Baltic state of 2m citizens has just taken over the presidency of the European Union’s Council of Ministers, and the government is giddy with excitement.The presidency rotates among member countries every six months, offering a chance to steer some of the EU’s political and legislative work. For minnows like Latvia it is a chance to bask in attention they rarely receive. For its time at the helm Latvia wants to focus European minds on three priorities: competitiveness, the digital single market and foreign policy. That may sound less than scintillating, and it is true that the presidency wields less power than it did before the European Council of heads of government appointed a permanent president. Yet it is worth paying attention to Latvia, for on two challenges that confront Europe in 2015—how to kick-start growth, and what to do about Russia—it has an interesting story to tell.Latvia’s economic adventures of the past decade make Spain, Ireland and Greece...