It's true that the Jews proselytised long after the destruction of the Temple- perhaps more than before. But it's also a bit offbeam to claim that European Jews were not descended from the Jews of Palestine. There were many waves of migration, in many directions and under many different impulses- mostly very unpleasant ones.

But it's also true that (i) the Palestinian Jews under the Ottoman Empire usually got on well enough with both Palestinian Moslems (many of whom are descended anyway from Jewish converts) and with the rather more bumnptious and aggressive Christians.

man could make cars run on potatoes

Sure an' didn't they do that in ould Ireland. The man eats the potatoes. That gives him the strength to cut the grass to make hay. The donkey eats the hay and pulls the car.