Hard to say these days, even for a billionaire hedge-fund manager like Ray Dalio.

On the one hand, America has a better system, better tech, and better universities. On the other hand, China "has us outnumbered" in population and pace of per capita income growth.

China, he explains, has not only become a powerful competitor. The US has changed, too.

"[The] America that I remember is a different, uh, and grew up with is a different America than it exists today in terms of like equal opportunity and the American dream."

Watch the GZERO World episode: Does China's rise have to mean America's decline?