Could Israel one day risk losing effective control of a vast tract of desert which its founding father said was key to its survival?
The country's first prime minister, David Ben Gurion, said that without the Negev, Israel would be hardly a state and hardly Jewish.
But 60 years on, new Zionist groups fear the wilderness which makes up more than half Israel's territory could eventually have an Arab majority population.
They are calling for huge state investment in the Negev to persuade more Jews to move there from the country's overcrowded central belt.
"If we don't work fast, we might find ourselves in a situation which is on the verge of catastrophe, with 80% of our land which is not disputed today," says Dany Gliksberg, a founder of Ayalim, an organisation which encourages students to live, and do voluntary social work, in the Negev, the south of Israel, and Galilee, its northern region.
The two areas, which together account for about 80% of Israel, have the country's highest proportion of non-Jewish citizens.
In Galilee, 56% are non-Jewish, mainly Arab. In the Negev, Bedouin Arabs make up a quarter of the population, but according to government statistics, they have the highest population growth rate in the world, doubling their numbers every 15 years.
In Israel's current election campaign, the future of the occupied West Bank, and domestic living standards, are two of the main issues. But Mr Gliksberg thinks more attention should be paid to what he regards as a ticking time bomb:
"The Negev and the Galilee are one of the biggest missions we have today in Israel," he says. "If we lose 80% of our land, both on the social and economic side, and of course eventually on the demographic and political side, then I think we lose our right to exist as a country for the Jewish people."
Ben Gurion's dream was of five million Jews living and working in the Negev. But today they are still only about half a million, and the relative lack of jobs and services makes it hard to persuade more to move to the barren region.
Ayalim, which means "Gazelles", is one of a number of movements formed in recent years which aim to recapture what they see as the ideals and pioneering spirit of early Zionism.
It was founded in 2002 by Mr Gliksberg and four friends who had just finished their military service. They pooled their army discharge grants and bought a prefab which they put up on the edge of the desert in Ashalim, south of Beersheba.
Today Ashalim is the site of one of the organisation's "student villages". Together they house 1,000 young people - though they have applications from six times that number. Much of the building work is done by students themselves.
"To build with your own hands, to feel the brick, the sand, to build your own house, to plant your own tree, to pave your own path, this is something that will get you connected to the ground," says Ayalim worker Yakir Keren.
One of the places its volunteers work is a nearby Bedouin village, where they teach Arab children to grow plants in a school greenhouse.
"The challenges we have today in the Negev are above the conflict," Mr Keren says. "To be a settler and a pioneer does not mean you have to segregate yourself. It starts from setting a personal example, so that others can follow you."
But land use in the Negev has become a serious cause of conflict between the government and many Bedouin, who say their families have wandered and farmed the desert for generations.
Israel has built towns specially for them, and is now building more - in full consultation, it says, with Bedouin representatives. But it says many Bedouin in other places are living illegally on state land.
Israeli government spokesman Mark Regev says the official policy - known as the Prawer Plan - of moving Bedouin to planned communities is specifically intended to ensure they get a better allocation of national resources than in the past:
"One of the primary problems we've had till now is that the Bedouin haven't had ownership of the land they're on, and through the Prawer Plan we want to bring a situation where the Bedouin sit on land that they are legal owners of, and this is a form of empowerment that, together with parallel policies of investing in education and healthcare and other aspects of Bedouin infrastructure, we hope will bring the Bedouin into the mainstream."
But in one particularly controversial case, Bedouin houses in the former village of al-Arakib have been repeatedly demolished by the authorities in the course of a protracted legal battle over ownership.
Awad Abu Freih is among those who saw his family home destroyed. Professionally, he is an example of how Bedouin can succeed in Israeli society. With a PhD in chemistry, he lectures to mixed classes of Jewish and Arab students at a college in the Negev.
But he is deeply critical of state policy towards his people:
"They push us into cities," to concentrate us," he says, standing on a pile of stones which is all that is left of the home where he grew up. "They want a lot of Bedouin on a very small amount of land, and a few Jews on a big amount of land."
Like many Bedouin, he would like to have a farm. But he says Jews find it easier than Bedouin to acquire land for agriculture, because of the policy of encouraging Bedouin to live in towns.
"Why can't Bedouin live with camels, when Jewish people can?" Mr Abu Freih asks. "It's our profession to milk camels. But now I drink camel milk from Jews."
Dany Gliksberg of Ayalim says a Jewish majority in the Negev is essential to preserve the democratic nature of the state. Otherwise, he says, "we will be a minority ruling a majority of non-Jews".
His organisation is getting increasing political backing from the government, with two visits from Prime Minister Binyamin Netanyahu in recent weeks.
Israel says its Arab and Jewish citizens have equal rights under the law. But Jewish civil rights activist Ofer Dagan, of the Negev Coexistence Forum, says that in practice land policy in the Negev gives Bedouin fewer opportunities than Jews:
"The argument that we have to Judaise the Negev in order to ensure the existence of the Jewish democratic state is just simply not true. Because it may serve the purpose of making it a Jewish state. But it for sure won't be a democratic state.
"The danger that is already happening is that Bedouin society is gradually losing its faith in the authorities of the state, and we are starting to see a few violent incidents between Bedouin people, who are most of the time very peaceful patient people, and the authorities of the state - and I think it's a great danger to the future of this area," he says.
Watch Newsnight's Tim Whewell's report on BBC iPlayer. Newsnight is broadcast weekdays at 2230 GMT on BBC Two.