"Re-established," Rebecca corrects me, as there was a Jewish presence in this area prior to the declaration of Israeli statehood in 1948, but those Jews were forced out by Arab riots in 1929 and again in the 1930s. When Jordan occupied the West Bank following the Israeli War of Independence, Jews could not settle here, but following the Six-Day War, they returned, led by one of the children of those earlier evacuees. Since then, Alon Shevut has thrived, boasting a population of some 650 families — mainly modern Orthodox and religious Zionist — and a winery, in addition to the academy.

The total population of the Etzion communities stands at well over 50,000-mere trivia in another context, but what such statistics measure are of the essence here in the West Bank. The much-reported dance of outpost construction and forced removal misses the real development: demography.

Nowhere is this more evident than in Modi'in Ilit, a 20-minute car ride from Tel Aviv. Although the Green Line divides secular Modi'in and its suburb, Modi'in Ilit, there is no disruption to the journey nor any indication that any border has been crossed. There is no checkpoint or military presence. I wasn't even aware we had crossed into Samaria until my guide, Ephraim, pointed it out.

Modi'in Ilit is the largest single Israeli community in the West Bank. "Settlement" is a misnomer: with some 55,000 Israelis here, the government has granted Modi'in Ilit the status of city. Unlike in Alon Shevut, the residents here are predominantly ultra-orthodox, or hareidi: their traditional black garb — reminiscent of eastern Europe and familiar to any visitor of the Jewish communities of London or Manchester — is an immediate giveaway. The ultra-Orthodox presence in Yesha is a relatively new phenomenon, and they now constitute a third of the Jewish population here.

We drive around. The area is fairly large, but, as in Tel Aviv, the preference here has been to build upwards; adorning the hills are unassuming apartment blocks of Jerusalem stone (imitation, probably). Even ignoring the residents, it is obvious that this is a hareidi town: the city is stark and utilitarian, the austerity disturbed only by coloured balcony railings and the occasional playpen. Batei midrash (study halls) and shtiebels (small synagogues) line the main road. There is even a branch of the famous Mir Yeshiva here. Some children ride up the pavement on bicycles, their tzitzit (religious tassels) flailing. Others are in a nearby playground.

"Children!" That's why Modi'in Ilit was built, Ephraim explains. Hareidim are known for their large families: since 1990, this burgeoning city has provided inexpensive housing for these ultra-Orthodox families hailing from brimful communities elsewhere in Israel. The population of Modi'in Ilit is expected to double within the next decade. This is the "natural growth" we hear so much about: these communities can grow rapidly thanks not to immigration, but to reproduction.