A handout photo made available by the Iranian Navy office on February 23, 2019, shows Iranian Navy submarines sailing during an Iranian navy drill in the Gulf of Oman, on February 22. (Photo by IRANIAN NAVY OFFICE / AFP/Getty Images)
US missile destroyer USS Donald Cook (DDG-75) is docked in the Ukrainian Black Sea port of Odessa, after it was moored early morning on February 25, 2019 to take part in joint exercises with Ukrainian Navy ships. (ALEKSANDR GIMANOV/AFP/Getty Images)
A Turkish military helicopter hovers over commandos during the Winter 2019 Combined Joint Live Fire Exercise in a mountainous area near Kars, eastern Turkey, on February 21, 2019. (ADEM ALTAN/AFP/Getty Images)
A handout photo made available by the Iranian Navy office on February 23, 2019, shows an Iranian Navy missile launch during a military drill in the Gulf of Oman. (Photo by IRANIAN NAVY OFFICE / AFP/Getty Images)
An Embraer jet (C), mounted with a DRDO NETRA, an Airborne Early Warning and Control System (AEW&CS), is escorted by Sukhoi SU-30s during a flying display on the inaugural day of the five-day Aero India 2019 airshow at the Yelahanka Air Force station, in Bangalore on February 20, 2019. (MANJUNATH KIRAN/AFP/Getty Images)
A soldier stands next to a Russia made tank T-55 standing aboard a train that has begun a journey throughout Russia to display war trophies taken by military engineers in Syria, including defused explosives in Moscow, Russia, Saturday, Feb. 23, 2019. The train set out from Moscow on Saturday, Feb. 23, and is to travel to the Pacific city of Vladivostok before returning to the capital in time for Victory Day on May 9. (AP Photo/Alexander Zemlianichenko)
Marines hold security during a fast-roping exercise as part of visit, board, search and seizure training at Marine Corps Base Hawaii, Kaneohe Bay, Hawaii, Jan. 9, 2019. (Cpl. Isaac Cantrell/Marine Corps)
Turkish military helicopters maneuver during the Winter 2019 Combined Joint Live Fire Exercise in a mountainous area near Kars, eastern Turkey, on February 21, 2019. (ADEM ALTAN/AFP/Getty Images)
Russian officers stand inside a train carriage with "Syrian turning point" exhibition organized by Russian Defense Ministry at Kazansky railway station in Moscow on February 23, 2019. - The train with "Syrian turning point" exhibition, which houses unique military trophies captured from militants in Syria, departed from Moscow to visit sixty cities across Russia. (YURI KADOBNOV/AFP/Getty Images)
A Royal Air Force Tornado GR4 fighter jet takes part in air to air refueling during a farewell fly-past over Britain on February 19, 2019 in Oxford, England. Nicknamed the "Tonka" by aviation enthusiasts, the Tornado GR4 will took part in a series of flypasts to commemorate the aircraft's contribution to defending the UK as it is retired from service. The fighter first saw service in service 1979 and was first used in combat during the first Gulf War and most recently supporting the war against ISIS in Iraq and Syria. (Photo by Christopher Furlong/Getty Images)
Military vehicles with the US-backed coalition against the Islamic State (IS) group are pictured during an operation to expel the jihadists, in the countryside of the eastern Syrian province of Deir Ezzor on February 21, 2019. - US-backed Syrian forces are negotiating to evacuate civilians from the Islamic State group's last redoubt which now faces "inevitable defeat", the international coalition against the jihadists said today. (DELIL SOULEIMAN/AFP/Getty Images)
Rafale, a French fighter aircraft is seen displayed on the last day of Aero India 2019 at Yelahanka air base in Bangalore, India, Sunday, Feb. 24, 2019. (AP Photo/Aijaz Rahi)