Spaceport Tiering for Access Resiliency Act or the STAR Act This bill requires the Department of Defense (DOD), in coordination with the Department of Transportation (DOT), to submit to the appropriate congressional committees a report on the resiliency of space access infrastructure to meet national security requirements. DOT shall establish a tiered system for spaceports that categorizes their operation for planning, development, and expenditure of funds. DOT shall develop a plan, to be known as the national plan for spaceports , for developing spaceports in the United States. DOT shall publish such plan every two years. To the extent possible, the DOD shall make domestic military spaceports and spaceport facilities available for civil use. DOT, in coordination with DOD and the Department of Commerce, after providing an opportunity for public comment, shall submit to the appropriate congressional committees a report on the implementation of a spaceport improvement program.