This what i found hope this helped. if not let me know
The population of Puerto Rico traces its ancestry in mostly the Spanish colonists and the indigenous people of the island. They have mixed over time and gradually created a mestizo population, which became the dominant population on the island and still is. There are of course some other influences in the gene pool of the Puerto Ricans, with some of it being from the African continent because of the African slaves that were brought, but it is a small minority, and it is also a population that has been heavily mixed.
So that not one person is given so much power they can attack the rights of citizens.
Because he thought that they would help pull out of the great depression hope this helps