THOSE ANGUISHED NOISES emanating from Israel are the sound of the Begin government collapsing. The latest sequence came about like this: the mayor of Nablus on the West Bank told an Israeli official that, given the way Palestinians feel about the Israeli occupation, incidents of terro r could only be expected. When a distended version of this sad truth became public, the Begin government ordered the mayor, a pro-PLO activist, expelled -- though the substance of what he said was disputed, no hearing had been held and he was accused of no crime.

This patently arbitrary response at once elicited a massive outpouring of West Bank (and Gaza) solidarity with the mayor and the PLO. What feeble prospects existed of some West Bank cooperation with the Israeli-Egyptian talks on Palestinian autonomy have evaporated. The deportation order could yet be checked by the Israeli Supreme Court, but that would merely deepen the government's embarrassment.

It would not be the court's first move with that result. Only last month the court, acting on an Arab petition, ordered the dismantling of the Israeli settlement at Elon Moreh, near Nablus. Israelis cannot seize private Arab land without a legitimate military-security rationale, the court said. Elon Moreh had been established by Israeli right-wingers precisely to assert a claim to settle anywhere in biblical Israel, even in the Arab heartland. That decision, imposing major new limits on Israeli settlement, was historic.

In fact, the decision was doubly historic. For the court also said that any Israeli settlement in occupied territory is temporary -- the creature of a temporary military occupation. This makes the Camp David point -- one that the biblically minded Begin government has tried every which way to ignore and blur and override -- that the future status of the West Bank is open for resolution. The Israeli right realized instantly that the court had undercut its plans for new settlements now and permanent incorporation later. But Israel remains a country of the law, and the court's decision stands.

In sum, the Begin government's own clumsiness has solidified a strong, united West Bank stand against the occupation and against any cooperation with the restricted autonomy offered by Israel. The court has crippled the practical plans and political ambitions of the dominant part of the Begin constituency. The prime minister was in great political trouble anyway. Now his Palestinian policy, which is the main thing, has been proved to be a dead end. If there is a way out for Mr. Begin, it is not obvious.