You are generalizing when you say (all) Jews are paranoid about openly displaying their Jewishness and afraid to defend themselves.

In the rare instance where a Jew has to be in an area of a particular city or town that is known for its anti-Semitic sentiment, he or she will probably be cautious about a public display. Men may remove their yarmulkes and replace them with a hat or a cap and women might put their Star of David charm inside their sweater or blouse. These areas are becoming more and more rare. they are no longer the threat that they once were and, therefore, anyone who would deliberately hide their identity is doing so out of a conditioned fear.

I happen to live in a part of the county that is not particularly Jewish...we are very few, actually, and drive to the closest town that has a shul. However, many people know that I am a rabbi and a therapist and come to me BECAUSE I am a rabbi.
As a direct response to your query of how to change that "world" image, I will say that it has to be one person at a time and we have to begin with ourselves.