I doubt if there was such a thing as an index measuring competitiveness and innovation 100 years ago, but I think the US would have rated quite highly. The middle and late 19th century was a golden age for American invention. For example, the telephone (1876), the light bulb (1880), the telegraph (1884), the sewing machine (1853), and the airplane (1903)are just a few inventions that changed the world. In regards to the intellectual potential of the Chinese, I remember someone saying that he would take our Chinese (including Taiwan) against the PRC anytime. If we stop giving them technology so their rockets wouldn't explode on takeoff, they wouldn't be so advanced regardless of their domestic computer science graduates. Maybe we should bar them from attending Cal Tech and MIT.
Re foreign debt: The Economist lists it as $149.8 billion, 4th largest in the world. China is paying an annual debt service of $21.7 billion to pay on its foreign debt, 5th largest in the world. The US is not listed in the top 48 in the amount of foreign debt so China's investment in the US must not be all that significant
Forever is a long time. No one has claimed that America will always be dominant, but comparing China to the US and Japan is a bit premature. Ther bottom line is that China has a long way to go to become a devolped country let alone a superpower. They are not ten feet tall anymore than the Soviet Union was. I once heard someone say that the Soviet Union was either the most developed underdeveloped country in the world, or the most underdeveloped developed country in the world. Based on a visit to Beijing a few years ago, I think that applies to the PRC today.