It's the elephant in the living room.
Being a "Jewish State" is incompatible with the presence of a significant number of non-Jewish residents, and completely incompatible with a large (and growing) demographic of voting non-Jewish citizens.
What happens to Israel when the Israeli Arab population has grown to a voting majority?
It's the forced circumcisions and forcing Matzos down their throat at Passover that realy gets the non-Jews mad.