Why did Obama back down on political prisoners in the Cuba deal?

So Obama settled for very little of his demand that Cuba release all its political prisoners before normalization could even begin. And just to underscore the point, Cuban President Raul Castro made a defiant speech Saturday telling Obama and the United States they can forget about making Cuba into a different place. “Every country has the inalienable right to choose its own political systems,” Castro said, according to an account in the New York Times. “No one should believe that improving relations with the United States means Cuba renouncing its ideas.”

That doesn’t sound like a Cuban leader who plans to make many changes in exchange for greater U.S. recognition. And it appears the White House really isn’t expecting much, at least when it comes to the formerly critical issue of political prisoners.