Sand is, of course, correct and merely restating what every yeshiva child understands thoroughly by the time he has a bar mitzvah. The only frame of reference for Jewish identity is our faith as embodied in Torah Shebichtav and Shebaal peh - a definition now marginalized as but one stream ("Orthodoxy") among many. Indeed, it's likely that everyone in the world understands this simple reality except for those Jews desperately trying to escape their identity. Muslims understand it. Christians understand it. Both our friends and our enemies understand. The frantic contortion of Zionism was just one among many replacement theologies - destined for failure as all have been. A "Jewish Democratic State" can only mean one where the democratic process is subordinated to the maintenance/furtherance of the Jewish nature of the state, otherwise it is merely a democracy.
from the article: The Gospel according to Sand: We are not Jews