The American vice-president Joe Biden has secured the support of Romania for the revised US missile defence system. On Monday Biden obtained similar assurances from Poland.He is on a tour of central and eastern Europe to reassure countries that the new plan will serve their security interests. From Romania he will travel to the Czech Republic in search of Prague’s backing. At a press conference in Bucharest, Biden also pledged US support for young democracies in the region, notably Moldova. The original US missile shield plan drawn up by the Bush administration included bases in Poland and the Czech Republic to counter the threat of long-range missiles launched from so-called rogue states like Iran. But amid strong opposition from Russia, President Obama announced last month a “new approach” that would focus more on the menace of short- and medium-range missiles and involve sea-based missile interceptors.