Allowance. Uncle Sam allowance. Ask your great grandparents what life on Planet Earth was like prior to World War II. If it wasn't for President Truman, the people of what are now the rich nations of Europe would still be living in mud brick huts with thatched roofs, asking their uncle if they can borrow the donkey so that they can go to town to trade some goods. If you wanted to see electricity and gas powered automobiles, the solution was simple, go to London, Paris, Berlin, Vienna... The rest was barely out of the Medieval Age.
The only reason why China is rich is because we buy their products. Its economy has already been slowing for years, and despite the fears of it overtaking the US and all that that goes with it, we heard the same about Japan surpassing us economically as well for decades, and they they've been sputtering for how many years now? As wages in China rise and thus production costs, we'll just shift to buying cheap manufactured goods from India, then Bangladesh Vietnam...
Sure, Trump's shenanigans are causing other countries to shift to dealings with China instead, giving it a boost, but in a few decades, it will be yet another country that loomed on overtaking the ones that made it rich in the first place.