Any municipality owning lands that the government of the United States or any department or agency thereof, desires to use for national defense purposes may, in the discretion of the governing authorities of such municipality, lease such lands to the government of the United States of America or any department or agency thereof, for national defense purposes on such terms and conditions as the governing authorities of such municipality may agree upon, and in the event any lands are leased under the provisions of this section to the United States government, any department or agency thereof, such land shall be exempt from all taxation the same as if title thereto was vested in the United States of America.