philadelphia and families. but a stop in cuba, a cameo in the u.s. congress, a speech at the u.n., and the visit could create a trinity of tension. first havana where the vatican's influence helped ease 60-plus years of cold war animosity between the u.s. and cuba. >> there is a checkered and comply catted past, but that's the past. the pope is about living in the present and moving forward. >> reporter: during president raul castro's vatican meeting with francis earlier this year, the communist leader said he plans to attend every mass celebrated by francis. with castro in the pews, will the pope scorn the country's history of human rights violations and lack of religious freedom? pope francis told students in cuba thursday through video conference he'd like to see friendship between the u.s. and castro's communist nation saying -- >> translator: one of the most beautiful things is social friendship. this is what i would like to be able to achieve, social