The wealth shifted because the British Empire lost it's navy and thus it's force projection which made it lose it's way to control it's colonies and it handing it's colonies to the US in lend lease. That was combined with a guarantee of global seas protection from the US navy. CCP has zero force projection even over their local area of the world and are wholly dependent on imports from the rest of the world for its economy. The US could shut down the economy of China and send it in to millions of people dying famine by just putting some blockades up between the middle east and China and China would cease to be a country.