SEMPER FI Act Securing Military Personnel Response Firearm Initiative Act This bill directs the Secretary concerned to authorize an eligible member of the Armed Forces assigned to an Armed Forces recruitment center to carry a service-issue sidearm as a personal- or force-protection measure while on duty at the recruiting center, notwithstanding any federal, state, or local law or Department of Defense policy to the contrary. In lieu of authorizing eligible members of the Armed Forces to carry a service-issue sidearm, or in addition, the Secretary concerned may implement additional security measures for Armed Forces recruitment centers, including improved structural security measures. This Act shall not be interpreted to grant any member of the Armed Forces the authority to conduct civilian law enforcement functions within U.S. territory.