If the state of Israel is threatened, the assumption has been, that threat comes from outside – from militant Palestinian groups vowing to drive it into the sea or, more recently, from Iran. It is increasingly apparent, however, that the survival of Israel as a democratic and modern state is also threatened from within, specifically by its own ultra-Orthodox minority.

Economically, a far larger proportion of ultra-Orthodox Jews rely on the state for support than do other Israelis. They represent a diplomatic and security liability, spearheading unauthorised settlements and refusing military service on conscientious grounds. In their politics and social mores, they are deeply conservative, and their big families mean that their influence is growing faster than that of any other group.

This is leading to more and more conflicts within Israel itself. Scuffles in Beit Shemesh near Jerusalem this week and a protest rally against the harassment by ultra-Orthodox men of girls on their way to school are just the latest, and most virulent, instances of this culture clash spilling out on to the street. While many senior politicians, including President Shimon Peres, and the opposition leader, Tzipi Livni, have come out in outspoken support of Israel's secular democracy, their efforts only illustrate how difficult it is to defend moderation against zealotry of whatever kind. This is a struggle for the soul of Israel, and it is not going away.