The Pew report, administered after the wave of children of intermarriage born in the 1970s and 1980s had reached maturity, afforded the first possibility of an alternative look at the impact of intermarriage.

[This essay is from “Philanthropic Priorities in Light of Pew,” reprinted with permission from Contact, a publication of The Steinhardt Foundation for Jewish Life.]

By Theodore Sasson

A main focus of demographic concern since the publication of the National Jewish Population Survey of 1990 has been the rate of intermarriage. According to the new Pew Research Center survey, the rate of intermarriage began increasing rapidly in the 1970s, reaching about 55 percent for marriages between 1995 and 1999 and 58 percent for marriages between 2005 and 2013.

All else being equal, the mathematics of intermarriage are fairly simple. When two Jews marry each other they produce a single, inmarried household; when each marries a non-Jew, they establish two intermarried households. Because intermarriage produces twice the number of households, the result is a net population loss only if fewer than half of intermarried households produce Jewish offspring.

Until the release of the Pew report, social scientists had only one method of predicting the proportion of intermarried households that would raise Jewish children. Surveys asked intermarried parents whether they were raising their minor children as Jews. The National Jewish Population Study of 2000-01 reported that just 33 percent were doing so. Over the past decade, that statistic strongly bolstered the view that intermarriage contributes to population decline.

The Pew research group initially adopted the same general approach, albeit allowing for a greater range of possibilities. According to the survey, 20 percent of intermarried parents are raising their children Jewish by religion; 25 percent are raising them partly Jewish by religion; 16 percent are raising them Jewish not-by-religion; and 37 percent are raising them not Jewish.

The first wave of commentaries on the Pew report emphasized either the glass half-full or glass half-empty implications of these numbers. On the one hand, just one-fifth are raising children Jewish by religion – by implication, with some form of Jewish education and household observance. On the other, 61 percent are raising children with a Jewish identity of one sort or another.

But the Pew report, administered after the wave of children of intermarriage born in the 1970s and 1980s had reached maturity, afforded the first possibility of an alternative look at the impact of intermarriage. After publication of the report, I asked the Pew research team to look at the rate at which the young-adult children of intermarriage actually identified as Jewish. The results are displayed in Figure 1. From the older to younger generation, the proportion of adult children of intermarriage identifying as Jewish steadily increased, reaching 59 percent among Millennials (born after 1980). Twenty-nine percent of the adult children of intermarriage identified as Jews by religion; 30 percent identified as Jews of no religion.

The higher-than-expected level of retention of the adult children of intermarriage has had a number of effects on the demography of the American Jewish community. It enlarged the young-adult age cohort – making it almost as large as the baby-boomer cohort – and skewed the overall Jewish population toward the young. It drove an increase, from older to younger generations, in the proportion of Jews that are the children of intermarriage – among Millennials, half of all Jews are the children of intermarriage (Figure 2). And, along with other factors, including immigration and the increase in the Orthodox population, it contributed to overall Jewish population growth.

The retention of the children of intermarriage has also driven an increase, from the older to younger generation, in the share of the population classified by Pew as “Jews of no religion” (Figure 3). When asked in the survey screener about their religion, these are people who responded “none” but then, in response to further questions, indicated that they have a Jewish parent and consider themselves to be Jewish or partly Jewish “aside from religion.” Most Jews of no religion are the adult children of intermarriage, and the increasing rate of intermarriage during the 1970s and 1980s fully explains the increase in the no-religion portion of the population from the oldest to youngest generation.

In terms of their socio-demographic profile, the Jews of no religion look much like other non-Orthodox American Jews: They tend to be politically liberal, college educated and avoid non-Jewish worship services. However, their level of engagement in all aspects of Jewish life – secular as well as religious – is substantially lower.

If not a demographic guarantee, the higher-than-expected rate of Jewish identification among the adult children of intermarriage is nonetheless a significant milestone. The rate at which young-adult children of intermarriage identify as Jewish exceeds the rate at which their parents claimed to be raising them as Jewish in the NJPS 2000-01 survey. This fact likely reflects a variety of dynamics including the increasing social prestige associated with being Jewish in America and the increasing reach of young-adult engagement initiatives.

Looking ahead, the philanthropic priority should be to maximize the proportion of children of intermarriage who are raised as Jews and then to keep the door open for young adults not raised as Jews to find their way into Jewish life as adults. The programmatic vehicles for accomplishing these goals are largely known. The critical programs are not the ones geared to the intermarried and their children; rather, they are the programs that engage a broad range of Jews of all backgrounds: Jewish preschools, summer camps, youth groups, Hillels and Israel trips. And in addition to these programs, there is a great need to expand innovative cultural, social and educational initiatives geared to young adults and situated in the neighborhoods where they work and live.

Failure to draw intermarried families and their children into the heart of American Jewish life will ensure that the prognostications of the demographic pessimists will eventually come true. Success, however, will ensure the opposite result: a flourishing and vital Jewish community in the next generation and beyond.

Theodore Sasson, Ph.D., is author of “The New American Zionism” (NYU Press, 2014). He is a senior research scientist at the Cohen Center for Modern Jewish Studies, a professor at Middlebury College and a consultant to the Mandel Foundation.