In a recent essay in these pages, Colin Brazier recalled a fascinating conversation he and I had in 2019, as part of a BBC documentary on large families. Like him, I was also struck by the fact that we come from very different backgrounds — he is a religious Catholic — yet firmly agree that in contemporary Western society, a positive attitude towards multiple child families is sorely lacking.

In his essay, Colin convincingly sets out the positive arguments in favour of siblings. Yet one line in his piece stands out. Quoting the demographer Paul Morland, he observes that, “The Chassidic Jews in Israel have among the highest fertility rate of any people in the world, [whereas] the secular Jews in America have among the lowest fertility rates.”

Reading that line both disturbed and perplexed me. It would be eminently understandable if fertility rates among secular Jews were simply average. But why should secular American Jews have “among the lowest’ fertility rates in the world?”

Assuming there are no dramatic medical reasons for this phenomenon, there can only be one plausible explanation. Secular Jews are increasingly opting to have no, or fewer, children, by choice. And they are doing so with a zeal matched by few other societies, even in the West.

There are, of course, many and varied reasons why people choose to delay or postpone starting a family. Particularly in America, there are real concerns over job security and the financial burden of the inordinately expensive cost of childcare, for example. But that alone does not explain, as put by leading historian of American Jewish history, Jack Wertheimer, the fact that, “Jewish women in the United States are significantly less fertile than their white, Gentile counterparts”.

Instead, I worry that there may be something altogether more disturbing at work. Sadly, there are increasing numbers of Jews who equate in-vogue values of the liberal left with Jewish values. And when that happens, as is often the case with those who were born into one particular value system and then discover an alternative, they become crusaders for the new cause. In this case, that means Jews proudly opting to have even fewer children than their non-Jewish secular neighbours, and whilst doing so, publicly declaring that they are motivated by noble, selfless, considerations of overpopulation. Career first becomes, over time, career only.

The truth, however, is that building a family in Jewish tradition, for those blessed with the ability to be able to do so, is more than just a mitzva. It is a life mission, a defining element of what it means to be Jewish. That is why no amount of crusading on the part of liberal eco-warriors regarding the damaging effects of overpopulation will transform limitations on childbearing on these grounds into a traditional Jewish value. Just as intellectual gymnastics on the part of liberal Jewish organisations cannot redefine the principles of Jewish faith in close alignment with liberal social theory or populist political movements.

Instead, we should be honest with ourselves and simply say it how it is. Ultimately, key decisions in life are a series of value judgments. Whether we are conscious of them or not, those judgments are always informed by an underlying value system of one sort or another.

One value system consists of the collective wisdom of contemporary liberal social thinkers. To dispute the doctrinal teachings of these theologians of woke and cancel culture is nothing short of heresy. And the slope leading from populist childless environmentalism is not merely slippery, it is a free-fall off the edge of a sheer cliff. Give in to the overpopulation argument on these grounds and those other progenies of modern liberal wokeness — anti-shechita, anti-brit milah and anti-Israel — are just a few steps behind.

Alternatively, as Rabbi Sacks, of blessed memory, would say, when all else fails, we can simply read the instructions. Remarkably, we actually have our own heritage and traditions — instructions for life no less — to help navigate complex value judgments in life. We can reject the desperate drive to be more liberal than the liberal prophets themselves. Instead, we can choose to benefit from the distilled wisdom of generations upon generations of our Jewish ancestors, who, based on the values of the Torah itself, taught us to value family, the Jewish home and that very tradition above all else.

Yoni Birnbaum is the rabbi of Kehillas Toras Chaim shul, Hendon.