Conditions under which Israelis would need to flee would probably involve serious use of weapons of mass destruction (also known as “doomsday” weapons). There would be no where to flee. There is a reasonable chance Americans would also have to flee. While it is unknown if the Israelis developed effective bio-chemical weapons, there is a saying each country bases strategy on the last war, and the worst case secenario, which leads one to suspect the Israeli “model” was how to survive if World War II went the other way, which suggests the Israelis would have developed weapons of mutually assured destruction.
Perhaps this is an argument to develop interplanetary travel.