divisive - dih-VIH-siv - causing disagreement or hostility within or between groups that is likely to create a split

Example: Columnist Gail Collins, writing about the issue in the locker room of the Washington Wizards (formerly called the Bullets), stated, 'Gun control may be seen as a divisive issue, but most can agree that the Wizards players should not have brandished, during an argument, five handguns in their locker room.'"