Han is at least as powerful as Roman Empire or even surpass it in wealth. Han Empire stretched from modern day Korea to Kazakstan in Central Asia and beyond. Huns were defeated, annhilated by Chinese force. The rest fled west to Europe. Chinese civilization reached zenith under Tang Dynasty in 2nd half of 7th century.
Chinese supremacy is unchallenged for a hundres years.
Chinese troops campaigned west of pamir Two times penetrate Himalayas into Nepal and Northern India. Tibet was submit into a vassal state. By destory the Eastern Turks, entire Mongolia was diretly incorporated into China itself. In a few years, Chinese control a far-flung empire that stretch from Shaklin island in Siberia to Caucus Mountains. Includes all modern day China, Mongolia, Siberia, Korea, North Vietnam, Nepal, Kazakstan, Uzbekstan, Turkmeinstan.