A spot in the final of the World Cup had just been secured, but Argentina’s football players wanted to declare another victory over England, whom they had just defeated 2-1 in the semifinal. Sweaty shirts off, they paraded on the field with a banner that read: “Las Malvinas son Argentinas”, translating to “The Falklands are Argentinian”.The islands, British territory, have for decades been a source of simmering tensions between the United Kingdom and Argentina, which claims them. In recent years, the governments of the two countries have mostly tried to limit those differences to formal positions, without escalating the dispute.The…