For all its historic import and feel-good photo shoots, President Obama’s visit to Havana played out on familiar terms. Obama and Cuban president Raúl Castro traded barbs about human rights abuses, Obama pressed for more avenues for the flow of private capital, and both leaders called for an end to the US trade embargo.

Castro also urged the US to return the Guantánamo Bay Naval Base to Cuban hands, drawing focus to an oft-ignored obstacle to the normalization of relations between the old enemies. Castro’s request is nothing new: Cubans of all political stripes have long demanded the base’s return, and since 1960, Havana has refused to cash the $4,085 lease payment Washington sends each year, alleging the lease is illegal.

Yet even as Obama seeks to close GTMO’s infamous detention center, the White House has made clear that it has no intent to return the base — despite Ted Cruz and Marco Rubio’s paranoid claims to the contrary.