re: #2 Bob Levin

Of course, they were born Jewish, but you can lose it. The Torah has certain specific instances where such a change in status occurs, but to me, the salient point is that such a change CAN occur.

There is no point at which you can lose your Judaism. “Yisrael af al pi sh’chata, Yisrael hu.”

Where exactly in the Torah do these “specific instances” occur?

I do think there is a point at which a person loses the right to utter the words “as a Jew” but unfortunately most of those who preface their anti-Israel, anti-Zionist comments will begin with that phrase.