<Tr> <Th> 12 </Th> <Td> </Td> <Td> Peter Buell Porter </Td> <Td> New York </Td> <Td> May 23, 1828 </Td> <Td> March 9, 1829 </Td> </Tr> <Tr> <Th> 13 </Th> <Td> </Td> <Td> John H. Eaton </Td> <Td> Tennessee </Td> <Td> March 9, 1829 </Td> <Td> June 18, 1831 </Td> <Td> </Td> <Td> Andrew Jackson </Td> </Tr> <Tr> <Th> 14 </Th> <Td> </Td> <Td> Lewis Cass </Td> <Td> Ohio </Td> <Td> August 1, 1831 </Td> <Td> October 5, 1836 </Td> </Tr> <Tr> <Th> 15 </Th> <Td> </Td> <Td> Joel Roberts Poinsett </Td> <Td> South Carolina </Td> <Td> March 7, 1837 </Td> <Td> March 4, 1841 </Td> <Td> </Td> <Td> Martin Van Buren </Td> </Tr>

When did secretary of war became secretary of defense