Peacekeeping operations were initiated to sustain global peace and security immediately after World War II with the establishment of United Nations. Today there are two common approaches, Westphalian and post-Westphalian, for the prevailing peacekeeping activities around the world. The Republic of Turkey, one of the supporters of a post-Westphalian model of peacekeeping operations, opened the door for peacekeeping operations with the Korean War against the expansion of Communism. Turkey has subsequently participated in a total of 26 peacekeeping operations and observer missions directly under UN command and other international organisations such as NATO and the OSCE since 1950.