Maradona captained Argentina again in the 1990 World Cup in Italy to yet another World Cup final. An ankle injury affected his overall performance, and he was much less dominant than four years earlier. After losing their opening game to Cameroon at the San Siro in Milan, Argentina were almost eliminated in the first round, only qualifying in third position from their group. In the round of 16 match against Brazil in Turin, Claudio Caniggia scored the only goal after being set up by Maradona.
In the quarter-final, Argentina faced Yugoslavia in Florence; the match ending 00 after 120 minutes, and Argentina advancing on penalty kicks, despite Maradona missing one in the shootout with a weak shot to the goalkeeper's right. The semi-final against the host nation Italy at Maradona's club stadium in Naples, the Stadio San Paolo, was also resolved on penalties after a 11 draw. This time, however, Maradona was successful with his effort, daringly rolling the ball into the net with an almost exact replica of his missed shot in the previous round. At the final in Rome, Argentina lost 10 to West Germany, the only goal being a penalty by Andreas Brehme in the 85th minute after a controversial foul on Rudi Vller.
Having previously been vocal in his support of neoliberal Argentine President Carlos Menem and his Harvard University-educated economist Domingo Cavallo, Maradona has shown sympathy to left-wing ideologies. He became friends with Cuban leader Fidel Castro while receiving treatment on the island with Castro, stating, "Diego is a great friend and very noble, too. There's also no question hes a wonderful athlete and has maintained a friendship with Cuba to no material gain of his own." He has a portrait of Castro tattooed on his left leg and one of Fidel's second in command, fellow Argentine Che Guevara on his right arm. In his autobiography, El Diego, he dedicated the book to various people, including Castro. He wrote, "To Fidel Castro and, through him, all the Cuban people."
Maradona was also a supporter of former Venezuelan President Hugo Chvez. In 2005, he came to Venezuela to meet Chvez, who received him in the Miraflores Palace. After this meeting, Maradona claimed that he had come with the aim of meeting a "great man" ("un grande" in Spanish), but he had met instead a gigantic man ("un gigante" in Spanish, meaning he was more than great). "I believe in Chvez, I am Chavista. Everything Fidel does, everything Chvez does, for me is the best." Maradona was the guest of honor of Chvez at the opening game of the 2007 Copa Amrica held in Venezuela.
Maradona has declared his opposition to what he identifies as imperialism, notably during the 2005 Summit of the Americas in Mar del Plata, Argentina. There he protested George W. Bush's presence in Argentina, wearing a T-shirt labeled "STOP BUSH" (with the "s" in "Bush" being replaced with a swastika) and referring to Bush as "human garbage". In August 2007, Maradona went further, making an appearance on Chvez's weekly television show Alo Presidente and saying, "I hate everything that comes from the United States. I hate it with all my strength." In December 2008, Maradona expressed admiration for Bush's successor, President-elect Barack Obama, and held great expectations for him.
With his poor shanty town upbringing, Maradona has cultivated a man of the people persona. During a meeting with Pope John Paul II at the Vatican in 1987, they clashed on the issue of wealth disparity, with Maradona stating, "I argued with him because I was in the Vatican and I saw all these golden ceilings and afterwards I heard the Pope say the Church was worried about the welfare of poor kids. Sell your ceiling then amigo, do something!" In September 2014, Maradona met with Pope Francis in Rome, crediting Francis for inspiring him to return to religion after many years; he stated, "We should all imitate Pope Francis. If each one of us gives something to someone else, no one in the world would be starving."
In December 2007, Maradona presented a signed shirt with a message of support to the people of Iran: it is displayed in the Iranian Ministry of Foreign Affairs' museum. In April 2013, Maradona visited the tomb of Hugo Chvez and urged Venezuelans to elect the late leader's designated successor, Nicols Maduro, to continue the socialist leader's legacy; "Continue the struggle," Maradona said on television. Maradona attended Maduro's final campaign rally in Caracas, signing footballs and kicking them to the crowd, and presented Maduro with an Argentina jersey. Having visited Chvez's tomb with Maradona, Maduro said, "Speaking with Diego was very emotional because comandante Chvez also loved him very much."
In October 2015, Maradona thanked Queen Elizabeth II and the Houses of Parliament in London for giving him the chance to provide "true justice" as head of an organisation designed to help young children. In a video released on his official Facebook page, Maradona confirmed he would accept their nomination for him to become Latin American director for the non-governmental organisation Football for Unity.