People talk about achdus. We are all one nation!!!
But what does it mean to be a Jewish nation?
היום הזה נהיית לעם – בכל יום יהו בעיניך כאילו היום באת עמו בברית.
היום הזה נהיית לעם THIS DAY YOU HAVE BECOME THE PEOPLE [OF HASHEM YOUR GOD] – On each day it should appear to you as though it were "today" that you have entered the covenant with him. [Rashi Devarim 27-9]
Our nationhood is defined by our entering into a Bris with Hashem. והמבין יבין.