First of all, being a lifetime resident of elected office and never having had a real job is NOT a position from which one should be demanding others to apologize for anything.
Then we have the status of US Senator from Vermont , big deal. How does that make you any better or have higher morals than anyone else in the country you want to apologize. I would suggest that being a Socialist US Senator in 2015 is a pretty poor example of having accomplished much in life at all besides accusing others of not living up to your socialist standards which you inherited from Saul Alinsky.
How about this Bernie, you lived on a kibbutz in Israel for a time. Since most socialists I know don’t like Israel but love hard left Palestinians why don’t you proceed our American apology for the Portuguese, Dutch, and English slavers bringing slaves to the Americas with a denunciation of Israel and unchained love for “Palestine.” Then you can renounce your complicity in helping “occupy” Palestine from the Kibbutz.
That would be a great start in having any credibility as a candidate for anything other than the college student, NY, Ct. , Ma., votes in Vermont you get to be a political sideshow.
Then we can give lefty Vermonters a chance to vote on a statewide referendum to return Vermont to the Indians and we will see how racist your political supporters are.