Will Israel have a religious majority?
Orthodox Judaism could become the dominant force within a generation, according to one forecaster.
The Knesset of the future? Orthodoxy looks set to exercise growing influence within Israeli society
Israel has more than enough to worry about - the uncertain outcome of the Arab spring, the paralysed peace process, not to forget the nuclear ambitions of the theocrats of Tehran. But according to Professor Arnon Soffer, there is something else that should be weighing on Israeli minds long-term.
Earlier this year the Haifa University social scientist produced a report projecting that within two decades, Israel will have a religious Jewish majority.
When Soffer says "religious", he means Orthodox. A prospect that, for him, represents not simply an interesting sociological phenomenon but a cause of deep concern. Unless there is a secular revolution, he has argued, the outcome will be growing poverty and a secular minority forced to adapt to a more religious society.
"Education will become religious education," he said. "Law will be tightly steered by halachah; the media will be revolutionised, doing away with much of the content broadcast today." If Israel's decision-makers did not act, he warned: "The Zionist vision will come to its tragic end and Israel will be back out in exile to face antisemitism and assimilation."
Soffer's alarmism may seem unwarranted - and some would dismiss it simply as scaremongering. But it is indicative of the secular-religious tensions that bedevil Israel in a way hard to envisage in the diaspora.
The growing influence of religion in contemporary Israel certainly would have scandalised some of the early Zionists who saw the Jewish national movement as a means not only to escape persecution but also to liberate themselves from "the chains of tradition". These radicals came to Zion not to replant the old faith but to create in the ancestral homeland a new way of Jewish life.
The rise of Israel's Charedi population - which Soffer predicts which will exceed a million by 2030 - presents a particular challenge. If Israel continues to grant yeshivah students exemption from military service at the same rate as now, then the IDF could lack sufficient manpower to defend the country in future. If Charedi men do not have the secular education to attain higher qualifications, then this may eventually affect Israel's ability to sustain an advanced economy.
There are, it should be said, a growing number of initiatives to encourage more Charedi men into the army and to enrol in vocational studies. The picture could have significantly changed in 20 years. But left unchecked, the trends will lead, Soffer says, to "an ever-increasing state of inequality, dissatisfaction and resentment".
Even if an Orthodox majority were to come to pass, however, that does not mean Israel would turn into a theocracy. Orthodoxy itself is made up of different strands and diverging views exist about the role of religion in society.
Chief Rabbi Lord Sacks, for example, is one of the more notable advocates of religion keeping its distance from institutions of state, even if there is no formal separation as in the USA. "Judaism must be depoliticised," he wrote in a recent book Future Tense, "and put back where it belongs, in civil society, far removed from all structures of power".
On the other hand, if your worldview is that the Jewish people's tenure in the Land of Israel depends on the observance of the mitzvot, you may well think it your patriotic duty to bring secular legislation closer in line with halachah. So some religious factions may become more emboldened in pushing for a conservative social agenda, on abortion, say, or gay rights.
As demographic changes intensify the debate over Israel's Jewish character, one issue is almost sure to resurface with all the contentiousness that it has kindled before: the very question of who is a Jew. Previous attempts by some Orthodox groups to narrow the definition in Israeli law have foundered over fears of driving a wedge between Israel and the diaspora, particularly its largest community, the United States, which still has a large non-Orthodox majority. But those who see themselves as the gatekeepers of Jewish peoplehood may be less minded in future to accept the status quo.
Faced with a resurgent Orthodoxy, the Conservative and Reform movements abroad may feel compelled to invest more heavily in Israel in an effort to extend their, so far rather limited, influence in the country - which if would in turn provoke a hostile reaction from some Orthodox quarters.
If Soffer has read the trends correctly, the future of Israel looks increasingly likely to be bound up with the direction of Orthodoxy. Which makes it all the more important what kind of Orthodoxy will prevail. Will it be the insular, sectarian strain represented by rabbis who say that Jews should not rent housing to Arabs?
Or the enlightened traditionalism espoused by Lord Sacks, compatible with liberal democracy, open to secular culture and supportive of a civil society which is able to "embrace religious and secular, Jew and Palestinian alike"?