Gunfire was brought to the steps of President Truman's Washington home, Blair House, as two assassins tried to kill the chief executive, November 1, 1950. One of the gunmen, Oscar Collazzo of New York, lay wounded at the bottom of Blair House's front steps after the president's police guard had finished their work, at the cost of one guards' life, Dec. 9, 1950. The second gunman was killed. (Photo by Harvey Georges/AP Photo)

Soldiers from the Nigerian Armed Forces take position and secure the streets in Lagos Island, Lagos, on February 27, 2023, after hoodlums had harassed market owners. Nigeria slowly counted more results on Monday after a tight election for the presidency of Africa's most populous nation as delays and accusations of manipulation fuelled tensions Nearly 90 million were eligible to vote on Saturday for a successor to President Muhammadu Buhari, with many hoping for a new leader to tackle insecurity, economic malaise and widening poverty. (Photo by John Wessels/AFP Photo)

Demonstrators march in Port-au-Prince on February 14, 2021, to protest against the government of President Jovenel Moise. Several thousand people demonstrated Sunday in the Haitian capital Port-au-Prince, saying the government was trying to establish a new dictatorship and denouncing international support for President Jovenel Moise. The protests were mostly peaceful, although a few clashes broke out between some demonstrators and police, who fired tear gas and rubber bullets. (Photo by Valerie Baeriswyl/AFP Photo)

A demonstrator catches fire after the gas tank of a police motorbike exploded during clashes in a protest against Venezuelan President Nicolas Maduro, in Caracas on May 3, 2017. Venezuela' s angry opposition rallied Wednesday vowing huge street protests against President Nicolas Maduro' s plan to rewrite the constitution and accusing him of dodging elections to cling to power despite deadly unrest. (Photo by Juan Barreto/AFP Photo)

U.S. Secretary of State John Kerry stands inside the historic Shackleton hut near McMurdo Station, Antarctica, Friday, November 11, 2016. Kerry became the highest-ranking American official to visit Antarctica when he landed for a two-day trip on Friday. He's been hearing from scientists about the impact of climate change on the frozen continent. Kerry's aides described the trip as a learning opportunity for the secretary of state. He has been receiving briefings from scientists working to understand the effects of climate change on Antarctica. Kerry has made climate change an intensive focus of American diplomacy during his term, and had previously spent decades working on the issue as a U.S. senator. Trump has called climate change a hoax and said he would “cancel” U.S. involvement in the landmark Paris Agreement on global warming. (Photo by Mark Ralston/Pool Photo via AP Photo)

A supporter of Venezuela's President Nicolas Maduro, with a doll depicting late Venezuela's President Hugo Chavez on his hat, reacts as he stands at the Plaza Bolivar near the building housing the National Assembly in Caracas, January 5, 2016. (Photo by Christian Veron/Reuters)

A riot policeman fires into the air during clashes with opposition supporters at a rally demanding a referendum to remove President Nicolas Maduro in Caracas, Venezuela, May 11, 2016. (Photo by Carlos Garcia Rawlins/Reuters)

Russian President Vladimir Putin (C) and Defence Minister Sergei Shoigu (back) attend a reception to honour graduates of military academies at the Kremlin in Moscow, Russia, June 28, 2016. (Photo by Alexei Druzhinin/Reuters/Sputnik/Kremlin)