And all this matters how? We live in a global, multi-national economy. Economic nationalism is a relic of the past. Nationality means next to nothing in business today. Either you're part of the global economy, or you're not.
Whether China has the tools to become a superpower matters because -- as best as I'm able to tell, anyway -- power still matters: states are still jockeying for more influence and seeking to limit the influence of others via a variety of channels, including but not limited to military, economic, and (perceived) cultural superiority, all aimed at securing their perceived interests in perpetuity. Has the 21st century thus far been different than the 20th in this regard, ever-increasing economic ties and all? I'd say not.
To the extent that that's true, the subject of the thread is pertinent. Actually, it's still pertinent even if none of what I've said is true, because it's a rebuttal of the fearmongers who think China is about to become a viable rival to US hegemony.
Given the growing gap between the haves and the haves not in the US, most people reading this in the US will see their, and their descendants, quality of life go down, while the international elite (of any nationality), will continue to prosper and further separate themselves from the have nots. If you live in a fly-over state, with a low cost of living, you may not realize what's going on, but if you live on the coasts or in DC, it's obvious.
This is an interesting issue that also needs to be discussed.