It's not the nation at fault, it's just those individual, filthy rich Saudi princes.

ISIS seems strong and well-funded. I saw videos online where they used car-mounted artillery pieces to storm a settlement. Although this conventional mode of warfare also means that they are playing on a field where the US is absolutely number 1. Al-Queda was hard to beat because they didn't operate out in the open, so ISIS should be a walk in the park in this regard. After their conventional forces are broken, I also suspect that they'll lose their appeal and popular support.