Marine Commandos (MARCOS) of the Indian Navy take part in a simulated hostage rescue operation at the Gateway of India during a rehearsal for forthcoming Navy Day celebrations in Mumbai on December 2, 2018. (PUNIT PARANJPE/AFP/Getty Images)
Kuwaiti and French army forces take part during the closing ceremony of a joint drill code-named "Pearl of the West", held at al-Udaira shooting range, 95 km northwest of Kuwait City, on November 29, 2018. - (YASSER AL-ZAYYAT/AFP/Getty Images)
Ukrainian servicemen on armored personal carriers (APC) take part in brigade tactical exercises with combat shooting near Goncharivske willage, Chernihiv region, not far from the border with Russia on December 3, 2018. - Tensions between Ukraine and Russia rose on November 25, when Russian forces seized three Ukranian navy vessels and their crew. Ukraine imposed martial law for 30 days in 10 regions that border Russia, the Black Sea and the Azov Sea on November 28. (SERGEI SUPINSKY/AFP/Getty Images)
Kuwaiti and French army forces take part during the closing ceremony of a joint drill code-named "Pearl of the West", held at al-Udaira shooting range, 95 km northwest of Kuwait City, on November 29, 2018. (YASSER AL-ZAYYAT/AFP/Getty Images)
A military honor guard team carries the casket of former U.S. President George H. W. Bush into the U.S. Capitol December 3, 2018 in Washington, DC. A state funeral for former U.S. President Bush will be held in Washington over the next three days, beginning with him lying in state in the Rotunda of the Capitol until Wednesday morning. (Photo by Win McNamee/Getty Images)
Pakistani military personnel take part in a drill during the tenth International Defence Exhibition and Seminar (IDEAS) in Karachi on November 29, 2018. (ASIF HASSAN/AFP/Getty Images)
Members of Iraq's Rapid Response military unit take part in a "counter-terrorism" training at a military base inside Baghdad International Airport on December 4, 2018. - The exercises are being held over a period of four months in cooperation with the Italian forces in Iraq. (AHMAD AL-RUBAYE/AFP/Getty Images)
The US military displays what it says are Iranian weapons, at Joint Base Anacostia-Bolling in Washington, DC, on November 29, 2018. - Senior US officials presented what the Pentagon called "clear and tangible evidence" that Iran is arming dangerous groups with "advanced weapons" and is fueling instability across the Middle East. (THOMAS WATKINS/AFP/Getty Images)
A picture taken near Urzuf village not far from the city of Mariupol, eastern Ukraine on November 29, 2018 shows Ukrainian tanks during military drills. - Ukraine's president imposed martial law in border regions on November 28, 2018 for 30 days in 10 regions bordering Russia, the Black Sea and the Azov Sea, after Russian forces seized three of Kiev's ships off the coast of Crimea on November 25, sparking the most dangerous crisis between the ex-Soviet neighbours in years. (PSEGA VOLSKII/AFP/Getty Images)
U.S. Marines install razor wire next to the U.S.-Mexico border fence on December 2, 2018 as seen from Tijuana, Mexico. Marines continued reinforcing the fence on the San Diego side of the border, with thousands of members of the migrant caravan housed nearby in Tijuana. (Photo by John Moore/Getty Images)
Ukrainian servicemen fire a gun as they take part in brigade tactical exercises with combat shooting near Goncharivske willage, Chernihiv region, not far from the border with Russia on December 3, 2018 - Tensions between Ukraine and Russia rose on November 25, when Russian forces seized three Ukrainian navy vessels and their crew. Ukraine imposed martial law for 30 days in 10 regions that border Russia, the Black Sea and the Azov Sea on November 28. (SERGEI SUPINSKY/AFP/Getty Images)
HAL Dhruv helicopters from the Indian Air Force (IAF) Sarang display team perform during the President's Standard and Colour Presentation to the IAF Number 118 helicopter unit and air defence college, at Air Force Station Borjhar in Guwahati on November 29, 2018. (KULENDU KALITA/AFP/Getty Images)
A Ukrainian sea border security force officer catches a rope as his unit mobilizes their armed vessels on the Azov Sea on November 28, 2018 in Mariupol, Ukraine. President Poroshenko has declared martial law in response to the attacking and seizing of three Ukrainian naval vessels by Russian forces. (Photo by Martyn Aim/Getty Images)
Ukrainain soldiers attends a military drills near Urzuf village not far from the city of Mariupol, eastern Ukraine on November 29, 2018. - Ukraine's president imposed martial law in border regions on November 28, 2018 for 30 days in 10 regions bordering Russia, the Black Sea and the Azov Sea, after Russian forces seized three of Kiev's ships off the coast of Crimea on November 25, sparking the most dangerous crisis between the ex-Soviet neighbors in years. (SEGA VOLSKII/AFP/Getty Images)