Pretty remarkable: 15-year-old American GM Jeffery Xiong won the 2016 World Junior Championship, and did so in comfort, clinching first place with a round to spare. After 7 rounds he was tied for first with two other players, but after scoring 4.5 points in the next 5 rounds the contest was over. He only drew in the last round, allowing top seed Vladislav Artemiev to narrow the gap by half a point (Indian GM Sunilduth Lyna Narayanan took third on tiebreaks with 9), but Xiong's 10.5/13 still won the tournament by a full point, and brought him within just five points of a spot in the top 100. This is a great achievement, especially since the tournament is a world championship for players under 20 years of age.
As this review article notes, the U.S. has the top two players in the world born in the year 2000 and the top two born in 2001. With three players in the world's top seven overall, we're in business.