up next, we speak with robert greg grieve i have on his book, "borderline citizens." >> older immigration history, tended to focus on nation-centered accounts, so we tended to frame immigration history in terms of the uprooted, the transplanted. and these ideas assumed that migrants crossed a clear boundary, crossing from their home country to the united states. and what i show this my book is that this border was very much constructed between the u.s. and puerto rico and that puerto rican migration is fundamentally shaped by u.s. colonial policy on the island. in the war of 1898, the u.s. invades puerto rico and the philippines. and after the war we will take these territories from spain as part of the treaty of paris. and so puerto rico and the philippines become the first kohl thinks of the united states -- colonies of the united states in the is sense that they are defined as unincorporated. and so this means that they're different from, say, arizona, texas, california, other territories that we had acquired that were expected to be future states and its people were expected to be fut

up next, we speak with robert greg grieve i have on his book, "borderline citizens." >> older immigration history, tended to focus on nation-centered accounts, so we tended to frame immigration history in terms of the