Yes you can use it in the US.
I'm surprised your camera didn't come packaged with the different AC cables. A Canon IXUS500 I recently purchased from Asia came with 3 AC cables with respective plug types for worldwide use. Similarly my D70 came with 2 AC cables/plugs.
However based on what you quoted as the back of the charger, I don't think you even need a different AC cord - just a pin plug adapter at the end to fit the US 2 prong plugs would suffice.