If Plan Dalet was not a plan to snatch land, why did Israel seize land it had not been given by the UN?

Einstein on Zionism: "I should much rather see reasonable agreement with the Arabs on the basis of living together in peace than the creation of a Jewish state. My awareness of the essential nature of Judaism resists the idea of a Jewish state with borders, an army, and a measure of temporal power, no matter how modest. I am afraid of the inner damage Judaism will sustain—especially from the development of a narrow nationalism within our own ranks, against which we have already had to fight strongly, even without a Jewish state. ... If external necessity should after all compel us to assume this burden, let us bear it with tact and patience."

One of the founders of Likud had been in charge of the group that Einstein and Arendt compared to Nazis.

You seem to have misunderstood my point. If Zionists had been like other immigrants who changed their names, they would've adopted names that were common in Palestine at the time.