I think you're missing the point by taking the 100-year number literally. Don't compare the Korea of today to Pittsburgh in 1912. Rather, note the difference between Pittsburgh in 1912 and Korea in 1912, and observe that in many ways the U.S. (and other Western nations) has been consistently ahead, by some varying but ever-present margin, for pretty much the entirety of that duration. There's no reason that won't change over time, and the fire in the bellies of the people in the other countries to become the best in the world is what will make it happen.