American Sovereignty Restoration Act of 2019 This bill directs the President to terminate U.S. membership in the United Nations (U.N.) and all affiliated bodies. It also ends U.S. participation in all U.N. conventions and agreements. Funds may be appropriated to facilitate U.S. withdrawal from the U.N. No funds may be made available for contribution to or paid to any U.N. body. No member of the U.S. Armed Forces may serve under U.N. command, and no funds may be used to support Armed Forces participation in U.N. military operations. The bill also repeals diplomatic immunity for officers and employees of the U.N. and for officers and employees of foreign government missions to the U.N. The bill repeals various acts related to the U.N., including the United Nations Participation Act, the United Nations Headquarters Agreement Act, the United Nations Environment Program Participation Act, and joint resolutions establishing U.S. membership in the World Health Organization and the U.N. Educational, Scientific, and Cultural Organization.