Construction continues on One World Trade Center (TALLEST BUILDING AT LOWER LEFT) as the memorial footprints of the twin towers are seen (BOTTOM C) on August 12, 2011 in New York City. Upon completion, One World Trade Center will be New York's tallest skyscraper, topping out at a symbolic 1,776 feet, with 3 million square feet of office space. More than 2,700 people were killed when al-Qaeda terrorists hijacked U.S. passenger jets and flew them into the twin towers of the World Trade Center on September 11, 2001. Nearly ten years after the crippling attacks on Lower Manhattan, business, tourism and new construction like One World Trade Center have rejuvenated the formerly devastated cityscape.(Photo by Mario Tama/Getty Images)

A model of the New Horizons spacecraft is seen at a live television program on NASA television celebrating the spacecraft's closest proximity to Pluto, at Johns Hopkins University Applied Physics Laboratory, site of the mission operations center, in Laurel, Maryland, USA, 14 July 2015. At approximately 7:49 am ET (11:49 am GMT), 14 July, New Horizons was scheduled to be as close to Pluto as the spacecraft will get; about 7,800 miles (12,500 kilometers) above the surface, following a journey of more than nine years and three billion miles. This is the first mission to the Pluto System and the Kuiper Belt. (Photo by Michael Reynolds/EPA)

Dancers wait backstage during a dress rehearsal for the new “THE ONE Grand Show” at Friedrichstadt-Palast in Berlin, Germany, September 21, 2016. From silver body suits with giant mohawks to revealing fishnet tops with huge feathers, colourful, extravagant costumes take centre stage at a new theatrical show in Berlin. French couturier Jean Paul Gaultier has swapped the Paris runway for the German stage to create some 500 costumes for “THE ONE Grand Show”, an 11-million euro ($12.2 million) production showcasing plenty of singing, dancing and acrobatics. (Photo by Hannibal Hanschke/Reuters)

“North and South Korea staged dueling war games Monday as threatening rhetoric from the rivals rose to the highest level since North Korea rained artillery shells on a South Korean island in 2010”. – Associated Press. Photo: North Korean soldiers with weapons attend military training in an undisclosed location in this picture released by the North’s official KCNA news agency in Pyongyang March 11, 2013. South Korea and U.S. forces are conducting large-scale military drills until the end of April, while the North is also gearing up for a massive state-wide military exercise. North Korea has accused the U.S. of using the military drills in South Korea as a launch pad for a nuclear war and has threatened to scrap the armistice with Washington that ended the 1950-53 Korean War. (Photo by KCNA/Reuters)

Models of Cold War-era Allied (L) and Soviet Bloc weaponry face one another at the new Bundeswehr Military History Museum (Militaerhistorisches Museum der Bundeswehr, or MHM) on October 11, 2011 in Dresden, Germany. The museum, redesigned by star architect Daniel Libeskind, traces Germany military history from 1300 to the present, including during the Nazi period and the Cold War, and also examines the influence of the military on popular culture. (Photo by Sean Gallup/Getty Images)

A female referee counts as member of Uganda's Soft Ground Wrestling is pinned to the ground during a training session at their camp in Mukono on February 28, 202. Uganda's Soft Ground Wrestling is getting attention worldwide and becoming an Internet sensation. Members showcase their wrestling skills on their YouTube channel, performing inside makeshift bamboo ring posts with string ropes and soil. Currently, Soft Ground Wrestling has 200 members, most of them from unprivileged backgrounds, and include both men and women training vigorously as they dream of becoming professional wrestlers. (Photo by Badru Katumba/AFP Photo)

An Afghan child practices walking with his new prosthesis at the International Committee of the Red Cross (ICRC), orthopedic center on September 10, 2011 in Kabul, Afghanistan. After more than 30 years of war and a decade since the 9/11 attacks in the United States, thousands of Afghans, both military and civilian, continue to pay a heavy price from the conflict. The ICRC center makes prosthetics for amputees and helps them, as well as Afghans with spinal injuries and children with congenital birth defects, to learn to walk. (Photo by John Moore/Getty Images)

“The Boeing X-45 unmanned combat air vehicle is a concept demonstrator for a next generation of completely autonomous military aircraft, developed by Boeing's Phantom Works. Manufactured by Boeing Integrated Defense Systems, the X-45 was a part of DARPA's J-UCAS project”. – Wikipedia

Photo: Two X-45A Unmanned Combat Air Vehicles (UCAV) are shown to members of the news media July 11, 2002 at Edwards Air Force Base, California. The X-45A, developed by The Defense Advanced Research Projects Agency and the Boeing Company, is the first unmanned system designed from inception for combat missions. (Photo by David McNew/Getty Images)