Modern Day Israel was not founded with a Biblical Foundation, the US was.
The founders tried to sell everyone on Uganda, Madagascar, and Grand Island, NY as a Jewish homeland. No sale. They ended up going with the Biblical boundaries of Israel, and that attracted Jews from all over the world, in spite of all that the British could do to blockade the coast and the borders. That is the foundation of Modern Day Israel, not the Balfour Declaration or any UN resolution, or any declaration by Ben Gurion. The foundation lies beneath the surface, but everything is built on that foundation, whether the government-du-jour will own up to it or not.