<Tr> <Td> </Td> <Td> Instrument of Surrender signed </Td> <Td> September 2, 1945 </Td> </Tr> <Tr> <Td> </Td> <Td> Treaty of San Francisco </Td> <Td> April 28, 1952 </Td> </Tr> <Tr> <Td_colspan="3"> <Table> <Tr> <Td> Preceded by </Td> <Td> Succeeded by </Td> </Tr> <Tr> <Td> <Table> <Tr> <Td> </Td> <Td> Empire of Japan </Td> </Tr> </Table> </Td> <Td> <Table> <Tr> <Td> Japan </Td> <Td> </Td> </Tr> <Tr> <Td> United States Military Government of the Ryukyu Islands </Td> <Td> </Td> </Tr> <Tr> <Td> United States Army Military Government in Korea </Td> <Td> </Td> </Tr> <Tr> <Td> Soviet Union </Td> <Td> </Td> </Tr> <Tr> <Td> Soviet Civil Administration </Td> <Td> </Td> </Tr> <Tr> <Td> Republic of China (1912--1949) </Td> <Td> </Td> </Tr> <Tr> <Td> Trust Territory of the Pacific Islands </Td> <Td> </Td> </Tr> </Table> </Td> </Tr> </Table> </Td> </Tr> <Table> <Tr> <Td> Preceded by </Td> <Td> Succeeded by </Td> </Tr> <Tr> <Td> <Table> <Tr> <Td> </Td> <Td> Empire of Japan </Td> </Tr> </Table> </Td> <Td> <Table> <Tr> <Td> Japan </Td> <Td> </Td> </Tr> <Tr> <Td> United States Military Government of the Ryukyu Islands </Td> <Td> </Td> </Tr> <Tr> <Td> United States Army Military Government in Korea </Td> <Td> </Td> </Tr> <Tr> <Td> Soviet Union </Td> <Td> </Td> </Tr> <Tr> <Td> Soviet Civil Administration </Td> <Td> </Td> </Tr> <Tr> <Td> Republic of China (1912--1949) </Td> <Td> </Td> </Tr> <Tr> <Td> Trust Territory of the Pacific Islands </Td> <Td> </Td> </Tr> </Table> </Td> </Tr> </Table>

Why did the us end its occupation of japan in 1951