The popular stereotype of the New York Jew has long been of someone who resides in the wealthy enclave of Manhattan's Upper West Side, reads The New York Times and votes for the Democratic Party with a religious devotion. Their Jewish practices largely consist of attending synagogue services on the High Holidays, sending the children to Jewish summer camps, and eating bagels and lox. This image, however, is now as outdated as Jewish vacations in the Catskills.

The New York Jews of today are more religious, more conservative, less educated and poorer than their predecessors. There are also more of them. Those are the main findings of a landmark study just released by the UJA-Federation of New York.

The study, conducted in 2011, is the largest of its kind ever undertaken in the United States. Its findings will be pored over for years to come. The significance of one of its findings, however, is immediately obvious and striking: New York's Jewish community is becoming increasingly Orthodox.

Thirty-two percent of Jewish households in the New York region are now Orthodox. Three decades ago, in 1981, the figure was just 13 percent. In New York City itself, the epicenter of the organized American Jewish community, 40 percent of the population is Orthodox. Most of these are actually ultra-Orthodox Jews.

Not only do Orthodox Jews now constitute a large proportion of New York's Jewish population, but they are also likely to become a majority in the future, if current demographic trends continue. The startling fact that two out of three Jewish children living in the New York region are Orthodox (even more in the city ) already suggests that the future Jewish community of New York will be increasingly religious, if not Haredi.

The implications of this for American Jewry, for Jewish politics and for Israel are profound. New York's Jewish population, which now numbers more than 1.5 million (out of a total American Jewish population estimated at 6.5 million ), is the largest in the world outside of Israel. This fact alone underscores the significance of its changing demography. Moreover, in Jewish communities across the United States, the proportion of Orthodox Jews is growing, as the non-Orthodox assimilate, intermarry and have fewer children.

A more heavily Orthodox American Jewish population spells the end of a long love affair with liberalism and the Democratic Party. Numerous polls indicate that Orthodox Jews are more politically conservative, and more supportive of the Republican Party, than non-Orthodox Jews. On a host of controversial social issues, including abortion, same-sex marriage and parochial schooling, they think more like Evangelical Christians than liberal Jews. This provides a huge opportunity for the Republican Party to do what it has tried and largely failed to do for the past three decades - prize American Jewish voters away from their historic attachment to the Democrats.

If the American-Jewish community becomes more right-wing and abandons its traditional support for liberalism, this will only further alienate the already shrinking number of non-Orthodox, liberal Jews in its midst. Rather than remain within the community, they could well become completely estranged from it, further cementing the religious and right-wing orientation of the organized Jewish community. Thus, the most important and influential Jewish community in the Diaspora could be slowly transformed from a bastion of progressive social values and Jewish religious pluralism, able to exercise a mostly benign influence upon Israel, to a redoubt of ultra-Orthodoxy, thereby strengthening the growing power of the Haredim in Israel.

In future, American Jewish support for religious pluralism in Israel, Arab civil rights and Arab-Jewish coexistence, Israeli-Palestinian peace and a host of other noble causes, could all be jeopardized by the growing religiosity of American Jewry. While there is nothing inherently contradictory between Judaism and support for peace, human rights and social justice, the fact remains that, in practice, Orthodox Jews are far less committed to these causes.

The gradual demographic transformation of New York's Jewish community is merely a microcosm of what is happening across the Jewish world. The Orthodox proportion of the European Jewish population is also growing. Haredim, for example, now make up an estimated 17 percent of Britain's Jewish population and account for three-quarters of all British Jewish births. It has been predicted that by 2050, half of all British Jews will be Haredi.

The same demographic trend is occurring in Israel, where, according to a Central Bureau of Statistics report last year, the ultra-Orthodox population is expected to rise to over 30 percent of the population in the next 50 years (from the present 10 percent ).

Is demography destiny? What does the increasingly Orthodox makeup of the Jewish population in New York, London, Paris, Jerusalem and elsewhere portend for the future of world Jewry? While one must be cautious about making long-term predictions based upon current trends, it seems safe to say that the predominantly secular Jewish communities of today, and their prevailing cultural and political values, are increasingly endangered.

Dov Waxman is an associate professor of political science at Baruch College and at the Graduate Center of the City University of New York. He is coauthor of "Israel's Palestinians: The Conflict Within" (2011), and is currently a visiting scholar at the Hebrew University of Jerusalem.