( CNN ) The VII Summit of the Americas was supposed to be all about the symbolic handshake between the United States and Cuba . But insert Venezuela into the mix and Panama City , Panama , quickly turns into a `` triangle of tension . '' Heads of state from 35 countries in the Western Hemisphere have met every three years to discuss economic , social or political issues since the creation of the summit in 1994 . Cuba has historically been the wrench in the diplomatic machinery , with some Latin American leaders threatening not to attend the Summit of the Americas if the United States and Canada did n't agree to invite President Raul Castro . The tide changed December 17 , 2014 , when President Barack Obama and Castro announced that more than five decades of Cold War rivalry was ending . Diplomats from both countries immediately began negotiations to establish embassies in Havana and Washington , and the attention immediately focused on the Summit of the Americas , where for the first time since the about-face , Obama and Castro would come face-to-face . The much anticipated handshake between Obama and Castro would steal all the headlines if it was n't for Cuba 's strongest ally , Venezuela . Venezuelan President Nicolas Maduro recently accused the United States of trying to topple his government and banned former President George Bush , former Vice President Dick Cheney , and Senators Bob Menendez and Marco Rubio from entering Venezuela . `` They ca n't enter Venezuela because they 're terrorists , '' Maduro said , blaming the American politicians for what he called terrorist actions in Iraq , Syria and Vietnam . The U.S. State Department said the allegations of U.S. involvement in a coup plot against Maduro were `` baseless and false . '' Later , Obama issued an executive order sanctioning seven Venezuelan officials for human rights violations and saying the country was a `` threat to national security . '' White House officials said every executive order includes that language , but it has sparked a fiery response from Maduro , who has been collecting millions of signatures demanding the repeal of the order . He also asked for repeal in full-page ads in The New York Times and in a Panama City newspaper . Maduro did n't stop there ; he has been rallying other Latin American leaders , including Bolivian President Evo Morales , Ecuador 's Rafael Correa and Nicaragua 's Daniel Ortega . But perhaps most damning for the United States -- and creating the `` triangle of tension '' at the summit -- Cuban Foreign Minister Bruno Rodriguez has sided publicly with Maduro . `` We reiterate our strong condemnation of the unacceptable and unjustifiable unilateral sanctions imposed against the sister nation of Venezuela and the continued foreign interference with the purpose of creating a climate of instability in that sister nation . We ratify our firmest support to the Bolivarian Revolution and the legitimate government headed by President Nicolás Maduro , '' Rodriguez said . While the world watches for the photo-op of Obama and Castro , it 's unclear if more Latin American diplomats will side with Maduro , and for America , the VII Summit of the Americas could go from `` mi casa es su casa '' to a walk into the lion 's den .
U.S. , Venezuelan relations threaten to overshadow Obama , Castro meeting . Comment: