A Mil Mi-24P helicopter of the Hungarian Air Force performs over the Danube river in Budapest on August 20, 2019 during an air show presented by the Hungarian Air Force as part of celebrations of Hungary's Foundation Day. - August 20 is a national holiday in Hungary, commemorating the foundation of the state by the country's first king Stephen I. (ATTILA KISBENEDEK/AFP/Getty Images)
A Syrian government tank drives next to a building near the town of Khan Shaykhun in the southern countryside of the rebel-held Idlib province on August 18, 2019. - A Turkish military convoy crossed into jihadist-run northwest Syria on August 19, it's path blocked by advancing regime troops as tensions soared between Damascus and Ankara, which said its forces were targeted by an air strike. (Photo by /AFP/Getty Images)
Philippine Navy sailors (L) march past their newly-acquired vessel, the Pohang-class corvette BRP Conrado Yap (PS39), as it prepares to dock at the international port in Manila on August 20, 2019. - The newly-acquired vessel from South Korea, measuring some 88.3 meters with a maximum speed of 32 knots, is capable of anti-submarine warfare equipped with sonar, torpedo launchers and depth charges. (TED ALJIBE/AFP/Getty Images)
Gripen fighter jets of the Hungarian Air Force fire their infrared countermeasure over the Danube river in Budapest on August 20, 2019 during an air show presented by the Hungarian Air Force as part of celebrations of Hungary's Foundation Day. - August 20 is a national holiday in Hungary, commemorating the foundation of the state by the country's first king Stephen I. (ATTILA KISBENEDEK/AFP/Getty Images)
An Israeli soldier stands holding up a rifle during clashes with Palestinian protesters following a weekly demonstration against the expropriation of Palestinian land by Israel in the village of Kfar Qaddum near the Jewish settlement of Qadumim (Kedumim), in the Israeli-occupied West Bank on August 16, 2019. (JAAFAR ASHTIYEH/AFP/Getty Images)
Aerial view taken on August 15, 2019 shows the special ship "Bottsand" of the German Navy during an exercise in the Baltic Sea near Rostock, northeastern Germany. - The crew of the ship trained a deployment in case of an oil spill after a possible collision of two ships. During the practice, the oil slick was simulated with 20 cubic metres of popcorn. (BERND WUESTNECK/AFP/Getty Images)
An MV-22B Osprey assigned to Marine Medium Tiltrotor Squadron 263 conducts flight operations during Integrated Training Exercise 5-19 at Marine Corps Air Ground Combat Center, Twentynine Palms, California, Aug. 11, 2019. ITX (U.S. Marine Corps photo by Cpl. Cody Rowe)
An homemade Male UAB unmanned aircraft systems is on display during the aerospace and defense industry exhibition at the World Trade Center in Taipei on August 14, 2019. - More 80 military weapon systems are on display during the exhibition between August 15 - 17. (SAM YEH/AFP/Getty Images)
Iraqi Kurdish Peshmerga forces using German-made assault rifles attend a training session by German military officers during the German Defence Minister's visit at a facility on the outskirts of Arbil, the capital of the northern Iraqi Kurdish autonomous region, on August 21, 2019. (SAFIN HAMED/AFP/Getty Images)
U.S. Marines with 4th Assault Amphibian Battalion, a unit based out of Tampa Bay, Florida, conduct vehicle recovery exercises with amphibious assault vehicles during UNITAS LX on the Brazilian Marine Corps Base of Ilha do Governador, Brazil, Aug. 19, 2019. UNITAS is the world's longest-running, annual exercise and brings together multinational forces from 11 countries to include Brazil, Colombia, Peru, Chile, Argentina, Ecuador, Panama, Paraguay, Mexico, Great Britain and the United States. (U.S. Marine Corps photo by Sgt. Booker T. Thomas III)
U.S. Army paratroopers assigned to 1st Squadron, 91st Cavalry Regiment, 173rd Airborne Brigade perform an airborne proficiency jump over Bunker Drop Zone in Grafenwoehr Training Area, August 14, 2019. (Spc. Ryan Lucas/Army)
U.S. Army paratroopers assigned to 2nd Battalion, 503rd Infantry Regiment, 173rd Airborne Brigade fire a M224 60mm Lightweight Mortar system under the cover of darkness during Exercise Rock Shock Two at Grafenwoehr Training Area, Germany, August 14, 2019. (Sgt. Henry Villarama/Army)
A military vessel sails near the Fort of Bregancon, the presidential summer residence in southern France, Monday Aug.19, 2019. French President Emmanuel Macron and Russian President Vladimir Putin are meeting in southern France to discuss the world's major crises, including Ukraine, Iran and Syria, and try to improve Moscow's relations with the European Union. (AP Photo/Daniel Cole)