That's true. The real problem the Israeli Left has is power is gradually shifting to religious Jews in Israel who have large families and who do not vote for secular parties and the anti-Jewish policies of the Left. That is why they play the demographic card and not out of concern for Israel's future but out of fear of their own political survival which can be enhanced by the destruction of settlements inhabited largely by religious Jews. So Israel's Left sees jettisoning Zionism not as a problem but as a solution to its own predicament of becoming a permanently outvoted minority in the not far distant future.
"Show me just what Mohammed brought that was new, and there you will find things only evil and inhuman, such as his command to spread by the sword the faith he preached." - Manuel II Palelologus