Just found a (English) letter from the Rebbe about this subject which I thought would be interesting.
Here’s an excerpt (you can find the whole thing on Chabad dot org):
“…Now, to come to the essential point. Why is it so important for Jews to have a Chanukah Menorah displayed publicly? The answer is that experience has shown that the Chanukah Menorah displayed publicly during the eight days of Chanukah, has been an inspiration to many, many Jews and evoked in them a spirit of identity with their Jewish people and the Jewish way of life. To many others it has brought a sense of pride in their Yiddeshkeit, and the realization that there is no reason, really, in this free country, to hide one’s Jewishness, as if it were contrary or inimical to American life and culture. On the contrary, it is fully in keeping with the American national slogan “e pluribus unum” and the fact that American culture has been enriched by the thriving ethnic cultures which contributed very much, each in its own way, to American life, both materially and spiritually.
Certainly, Jews are not in the proselytizing business. The Chanukah Menorah is not intended to, and can in no way, bring us converts to Judaism. But it can, and does, bring many Jews back to their Jewish roots. I personally know of scores of such Jewish returnees, and I have good reason to believe that in recent years, hundreds, even thousands, of Jews experience a kindling of their inner Jewish spark by the public kindling of the Chanukah Menorah in their particular city and in the nation’s capitol, etc., as publicized by the media.
In summary, Jews, either individually or communally, should not create the impression that they are ashamed to show their Jewishness, or they wish to gain their neighbors’ respect by covering up their Jewishness. Nor will this attitude insure their rights to which they are entitled, including the privilege of publicly lighting a Chanukah Menorah, a practice which has been sanctioned by the precedent and custom, as to become a tradition.
I also must point out that I do not think that a Jewish community can disregard its responsibility to other Jewish communities in regard to an issue of kind, which cannot remain localized, and must have its impact on other Jewish communities and community relations.
With esteem and blessing,
M. Schneerson
P.S. I trust you are aware of other instances involving Jewish practices in public, such as wearing a beard by Jewish servicemen in the U.S. military, wearing a Yarmulka in a court of law, etc., which Jews insisted upon, and won as their inalienable rights. Further information, if desired, may be obtained from the pertinent Jewish organizations, such as COLPA and others.
…It is difficult to imagine that after what had happened in Hitler Germany, some Jews will still entertain the idea that making themselves as inconspicuous as possible, concealing their Jewishness, they would gain favor with their gentile neighbors, whereas the opposite view is more widely recognized. Besides, antisemitism and prejudice require no outside causes. However, to expand on this topic here would be too much of a digression from our main subject.”