Waiting until the US is too dysfunctional to reliably bail them out of whatever wild bullshit they get themselves into. And then, starting a regional war. Great stuff.
Maybe shooting starving families for this long and everything going according to plan has convinced them that they're indestructible, and nothing can go wrong. It absolutely can. The US has managed to get successful outcomes out of about 0% of wars it has started in the Mideast, and the US is a hell of a lot more capable at these things than modern Israel is.