As it stands of course, it's original formation? Probably not, I'm not religious and so I'm not persuaded around claiming religious land. I don't think many liberals would if criticising zionism didn't have a backlash.
From the British side it was deemed neccesary due to needing a sphere of influence in the region. It was only a good bit later that it became more about fleeing the persecution across Europe and the British limited such immigration while it remained under our control. We actually turned boats back.
If there was a push now for another group of people who wanted to claim an area anywhere for themselves due to religious reasons and it required displacement of peoples there wouldn't be a single vote at the UN supporting it and no one would pretend it could be peaceful. So your question of supporting Israel's right to exist now is a completely different matter to the point i was trying to make, prehaps badly