Permission to Use the Magen David

Photo of a Star of David embroidered on a curtain in the old new synagogue in Prague is courtesy of maxjrosenthal, who published it on Flickr . 
This type of using the Magen David as an ornament on holy objects was one of the most common and prevalent in the last centuries and it penetrated the Orthodox Jewish world without someone stopping to think if at all it was allowable; only recently, in our generation, Rabbi Moshe Feinstein (1895 - 1986) who was the de facto supreme rabbinic authority for Orthodox Jewry of North America, was asked about it and he answered in his book Igros Moshe; (Epistles of Moshe) that is allowable since no body raised this question for the last centuries and no rabbinic authority had forbidden it.

So now orthodox Jews have a permission to use the Magen David. Secular Jews use it without any permission…