MOSCOW — Vladimir Putin’s Russia was always going to be a controversial host, but few could have imagined the turbulent situation that greets the 2018 World Cup. The annexation of Crimea, alleged U.S. election interference, the war in Syria and a poisoned spy in Britain are just a few of the storms surrounding the Kremlin before Putin officially declares the tournament open on June 14. Russia’s disputes with the United States and many European countries have galvanized Putin’s support at home against a backdrop of economic problems.