The US will never be a coalition member supporting an attack on Israel, or Taiwan for that matter. It will merely stand aside and allow it to happen.
Well, I guess it depends on the definition of coalition. We are providing money and military assistance to Egypt including licensed production of main battle tanks. We are providing delaying cover for Iran to perfect its nuclear weapons. We are shipping munitions and providing technical assistance to the Muslim Brotherhood and other Islamists in Syria. We may not be providing troops and pilots to directly attack Israel, but we are sure helping the formation of the Greater Caliphate which will attack Israel.