You mix up the religion Judaism with the ethnicity and culture. The jewish cultural and ethnic group is amongst the least religious peoples in the world, as many as 75% according to a study a few years back being atheist or agnostic (myself included).
The various jewish ethnic groups do have genetic ties to a geographic area and have diseases almost entirely unique to that ancestry.
That does however beg the question of whether ancestry is any sort of motivation to lay claim to an area of land in the first place. A question that can be endlessly debated and if accepted at face value opens up endless cans of worms. (How far back? Forever? Can it be lost? What if multiple peoples have claim to an area? etc. etc.)