The next war will be fought in the Persian Gulf against Iran and the excuse, true or otherwise will be the Iranian governments supposed drive to obtain nuclear weapons.
This event will gain momentum during the next 12 to 18 months with a strike against Iran coming in around 2 years imo.
Should Iran actually gain a nuclear weapon or a number of nuclear weapons, and were they to deploy such a device against Israel, this would cause a major exchange in the region with all out war being declared against Iran and frankly, should Iran deploy or otherwise use a nuclear weapon against Israel or the west, Iran would cease to be with a retaliatory strike the like of which has never before been seen.