Pope Francis and Donald Trump make little effort to conceal their disagreements. During the 2016 US presidential election, Francis suggested that Trump was “not Christian” for proposing to build a wall along the US-Mexico border – his campaign’s signature policy. Trump fired back by calling Francis’s comment “disgraceful,” adding: “No leader, especially a religious leader, should have the right to question another man’s religion or faith.” Francis was flying home from Mexico when he made the comments. Trump accused the Mexican government of turning the Holy Father against him, saying officials had “made disparaging remarks about me to the Pope”.