United States marks the 15th anniversary of the 9/11 attacks with solemn services to commemorate the victims of the deadliest terror strikes on U.S. Soil, which changed the world forever. Nearly 3,000 people were killed on September 11, 2001 when 19 Al-Qaeda suicide bombers hijacked four passenger jets, crashing them into the twin towers in New York, the pentagon in Washington and a field in Shanksville, Pennsylvania. It was the first foreign attack on the U.S. Mainland in almost two centuries and sparked us-led invasions of Afghanistan and Iraq where war rages on more than a decade later. Countries in the Middle East from Libya to Syria are engulfed in war, providing a fertile ground for Al-Qaeda affiliates to breed, and Europe has been tormented by attacks inspired by the I.S.