JERUSALEM — Prime Minister Benjamin Netanyahu faces a potentially formidable challenge to his hard-line rule — not from Israel’s civilian politicians but instead from its revered security establishment.

An extraordinary array of former top commanders are now criticizing Netanyahu in increasingly urgent terms, accusing him of mishandling the Palestinian issue and allying with extremists who are bent on dismantling Israel’s democracy.

On Tuesday, a group representing more than 200 retired leaders in Israel’s military, police, Mossad spy service, and Shin Bet security agency presented a plan to help end the half-century occupation of the Palestinians through unilateral steps, including disavowing claims to over 90 percent of the West Bank and freezing Jewish settlement construction in such areas.

The movement, called Commanders for Israel’s Security, reflects an increasingly widespread assessment that Israel is drifting catastrophically toward permanent entanglement with the Palestinians and conflict with the world community.

‘‘Things are getting worse and worse,’’ said Amnon Reshef, the group’s founder and a former commander of Israel’s armored corps. ‘‘What kind of future do we have here? What are we going to leave for our kids and young children?’’

Although a peace deal may not be possible at present, ‘‘still something can and should be done right now,’’ he said

The driving narrative is that the Holy Land’s 6 million Jews must find a way of detaching themselves from the roughly equivalent number of Arabs, most of whom live in the West Bank and Gaza and do not have voting rights in Israel.

Without the establishment of a Palestinian state, the argument goes, Israel will either eventually have to extend voting rights, formally absorbing the Palestinians in the occupied territories and destroying itself as a Jewish-majority country, or else be branded a nondemocracy destined to suffer comparisons to South African apartheid and risking a similar fate.

Surveys among youth around the world, even in the United States, suggest that cliff is coming.

Netanyahu and his Cabinet have shown little interest in changing course.

The prime minister does profess a theoretical desire for a two-state solution.

But in practice, his government busies itself with the Palestinian leadership’s shortcomings — publicizing incidents of ‘‘incitement’’ against Jews is a frequent theme — while continuing to settle territory, occupied in the 1967 Mideast war, where the Palestinians hope to establish a state.

Netanyahu and his supporters have had a fairly easy time fending off opponents, however prominent, dismissing them as ‘‘leftists’’ naive about the security imperative of territory in a tough Middle East.