When the war ended, Turkey was pressured by the Soviet government to allow Soviet shipping to flow freely through the Turkish Straits, which connected the Black Sea to the Mediterranean. As the Turkish government would not submit to the Soviet Union's requests, tensions arose in the region, leading to a Soviet show of naval force. The incident would later serve as a deciding factor in the issuing of the Truman Doctrine.[2] At its climax, the tensions would cause Turkey to turn to the United States for protection and NATO for membership.