Complex sentence: Another reason sometimes submitted for such establishment was to have a state where Jews would not be afraid of antisemitic attacks and live in peace, although such a reason is not a requirement of the self-determination right and therefore subsidiary to it in secular Zionist thinking.
Split into simpler sentences: Another reason sometimes submitted for such establishment was to have a state where Jews would not be afraid of antisemitic attacks and live in peace. But such a reason is not a requirement of the self-determination right and so is subsidiary to it in secular Zionist thinking.