Doesn't the "tanahk' say that Gaza is "promised" to the "tribe of Judah"?

Yes. And it does play a role in contemporary zionist thought,notwithstanding that most are atheists or what they call "secular jews". Ben Gurion was an atheist,but the Tanakh was his blueprint. Kurzer's clic biography makes it very clear that he felt the Gaza was important to seize and retain,and this was why. He didn't feel the Tanakh was divinely inspired but he had high regard for the "wisdom" contained therein,particularly the detailed instructions regarding the looting,pillage and plunder of Palestine. Gaza is promised to the tribe of Judah and the Gazans are to be liquidated. But it is emphasized that the Gaza has great strategic value and this was what interested Ben Gurion and what still interests present-day zionists. They obviously feel the admonition in the Book of Amos to destroy the Gazan people is Darn Good Advice.