<P> The term has also been used in music . </P> <Ul> <Li> The 1986 album The Ghost of Cain by the English rock band New Model Army features a track called "51st State", which refers to Britain under Margaret Thatcher for her perceived pro-Americanism . </Li> <Li> The 1986 track "Heartland" by English band The The describes an increasingly economically divided Britain as the 51st state of the US . </Li> </Ul> <Li> The 1986 album The Ghost of Cain by the English rock band New Model Army features a track called "51st State", which refers to Britain under Margaret Thatcher for her perceived pro-Americanism . </Li> <Li> The 1986 track "Heartland" by English band The The describes an increasingly economically divided Britain as the 51st state of the US . </Li>

When does puerto rico become the 51st state