You understand the concept of hegemonic power, it is intuitive. America has been the hegemonic power since the world wars ended the British hegemony. Going back in time you have to look at things more regionally as the world was not as connected up as it is today but regional hegemonic powers were clear as day too whether it was the Caliphate, Rome, Egypt, Persians, various Chinese dynasties, Mongolians, etc etc.

There is no question about what "number one" means. It is blatantly obvious, and what is happening is the same as has happened many many times before. One hegemony is in decline while a new power and its allies is in ascendancy. The world is changing and you need to recalibrate, this perspective has absolutely nothing to do with Putin.