Who isn't a Jew?
The definition of "Jew" is as unresolved now as it has been for the past 200 years. When Gabrielle Giffords, the Arizona congresswoman, was shot in the head by a maniac, the press in the US made much of her being Jewish. Her rabbi in Tucson said she was a committed Jewish member of her Reform congregation. But to many other Jews she is not. Although she has a Jewish father, her mother is Christian. Giffords is married to a non-Jew. She has not converted, and thus she is not Jewish by the standards of Orthodox and Conservative Judaism. Does it matter? Esther married a non-Jew too!
For thousands of years until the Enlightenment, everyone was defined by religion. The Jewish religious definition--a Jewish mother or conversion out of conviction--was the only criterion for Jews . There was no secular option. There were different periods in which things were either less rigid or more flexible, but that depended as much on external conditions as internal ones. Then new developments changed the picture.
As discrimination against Jews slowly began to thaw, more and more Jews and Christians wanted to marry each other, either for love or money. The only way to do that was for one partner to convert to the religion of the other. In most cases it was the Jew who married out, but in some cases the Christian wanted in, and in others the Jewish parents insisted on it. The problem was that conversion now became less a matter of conviction and more one of convenience or compulsion.
At the same time there were others born Jewish, like Spinoza, who despised Judaism and religion altogether. He was technically Jewish, by birth, but that was an accident he wanted nothing to do with.
Reform Judaism in the nineteenth century, developed a set of religious criteria of its own which made "conversion" a bone of contention. Zionism added another factor. The State of Israel decided to grant automatic citizenship to Jews through the Law of Return. "Never Again" would anyone be persecuted as a Jew without having a refuge. This purely secular, political decision defined Jews in the way Hitler did for the purposes of extermination. Anyone with a single Jewish grandparent qualified as a Jew.
At the same time, the State of Israel gave matters of personal religious status to the rabbinate, which imposed a purely religious definition. Young men and women given Israeli citizenship as "Jews" could fight and die for the Jewish state, yet neither marry nor be buried as Jews. Chaos.
The final nail in the coffin of a single religious definition came when American Reform Judaism accepted the patrilineal criterion in 1983 and thus cut itself off from the rest of religious Jewry. So that now there were Jews who were self-identified as Jews, but the Reform and Orthodox versions of religion became as different and as antagonistic to each other as Catholics were to Protestants.
Add this to the refusal of Orthodoxy to accept conversions it doesn't approve of (even Orthodox ones) and then setting the bar for conversion higher than ever before. Even more chaos. And amongst the Orthodox themselves there are factions and sects that recognize no one but themselves and a select few others on a good day.
And then there are secular Jews who worship at the altar of Woody Allen, Philip Roth, and Noam Chomsky. Some fund courses at American universities given by people who have nothing in common, know what they don't want but haven't yet worked out what they do and whose identity seems to be a whimsical mélange of birth and history, anger and dislocation.
The Jewish people now are more fragmented than they have ever been. There is no one definition that covers every variety. It is in practice true to say that anyone is a Jew who says he or she is. And why not? We are so few, we are under such constant assault all over the place, we should be grateful for anyone who wants to join our club and grateful for any friends and supporters we can get. Even the Megillah specifically includes and praises those who identified with the Jews (Esther 8:17).
But the fact is no one should be under any illusion that there is a master pass membership card. Many Charedi communities are only too delighted to take charitable donations from any kind of Jew even if they would not for moment entertain the possibility of marrying off a son or daughter to them. Your money will do, but not your body (or your soul). And ironically many Jews who have little to do with Judaism seem to feel that giving money to the very Orthodox is some kind of insurance policy.
This only becomes an issue if you want to change your Jewish subspecies. Each has its own ideology, standards of membership, rules and regulations, language and taboos, dress and head covering. It's the same with any club you want to join; to do so, you have to obey its rules. But thankfully in a free society no one is going to compel you. Denominations that do not honestly tell their members the reality of the situation are guilty of deception but that's their issue. Otherwise it's a free world. We need all the support and all the friends we can get. You want to be a Jew? Be my guest.
Here's an analogy. Soccer. You have professionals and amateurs, managers and trainers, goundsmen and administrators, casual spectators, travelling supporters and season ticket holders, agents and reporters. Those who make a living televising games, making sports equipment and clothes, promoting, designing and selling, all involved in one way or another with the sport. Yet the fact is that without the professionals, soccer would be little different from ping pong. Still soccer wants as many players as possible to be encouraged to play or watch the game. If anyone wants to train harder or play more often it is up to her or him. And if some want to switch to baseball, that's their business too. My only problem is with people who hate all soccer players for no good reason and rabbis who are too busy saying "no".