From Longman Dictionary of Contemporary Englishplay the race/nationalist/environmentalist etc cardplay the race/nationalist/environmentalist etc cardto use a particular subject in politics in order to gain an advantage a leader who is skilfully playing the nationalist card to keep power → play
Examples from the Corpus
play the race/nationalist/environmentalist etc card• Mugabe now plays the race card.• It will give the various groups and Tory Members who seek to play the race card the opportunity to do so.