China is afraid that Obama will destroy the value of the dollar completely and they will be left with a bag full of financial wallpaper material.
They're not afraid of that at all.
If the US Dollar is destroyed, the US is destroyed, leaving China either the sole world superpower, or perhaps one of two superpowers (the other being Russia).
They lose trillions of dollars, but it's cheaper than an actual war.
I think it is safe to say, we all are afraid of just that.