Israel's liberal left has been warning about this for decades – and now those cautionary words seem like prophesies. Lines of Israeli authors, academics and campaigners have long said that the ugly occupation of the Palestinian people would corrode Israel and derail its democracy. Human rights advocates repeatedly warned that a nation capable of meting out such punishing discrimination to another people would eventually turn on itself. And so it has.

The country is in thrall to such anti-democratic sentiment and mob rule racism, manifesting at such breakneck speed that it is hard to keep up. In the last few months alone two Arab citizens of Israel were "disappeared" by the state's secret police; an Arab member of the Knesset was stripped of her parliamentary privileges for being on the Gaza aid flotilla; and now a Palestinian man from Jerusalem has just been convicted of rape after pretending to be Jewish and having consensual sex. This verdict, in effect turning the obfuscation of race into a criminal offence, also reveals the extent to which Israelis consider Palestinians to be abhorrent. Meanwhile, the Israeli children of migrant workers are threatened with expulsion, as a government campaign warns against hiring foreign workers.

Zero tolerance for the "other" in Israel has widened to include anyone questioning a twisted concept of loyalty to the state. The Association for Civil Rights in Israel (Acri) lists 14 antidemocratic laws currently working their way through parliament, from the demand that Arab citizens pledge allegiance to a "Jewish democracy" to attempts to gag Israeli rights groups. Acri representatives are denounced as "Arab-lovers" and "traitors" when they attend parliamentary hearings. All this has widespread support – in fact, one of the few causes to bring thousands of Israelis on to the streets was a recent ultra-orthodox protest for the right to segregate Ashkenazi children, of European origin, from their Middle Eastern Jewish classmates.

Israeli human rights campaigners, appalled by this escalation of intolerance and racism, point to the three-week pounding of Gaza in 2008-9 as the opener of floodgates. Yael Ben Yefet, a Tel Aviv council member and the subject of a hate-deluge for supporting migrant workers, says that "something snapped" after the Gaza assault, in which about 1,400 Palestinians were killed. "It released Israel from the last of its humanitarian constraints," she says. "Now everything is possible."

Israel may have new thresholds after its assault on Gaza and its subsequent election of a zealously hard-right government. But what we're seeing today is just the unleashing, in more blatant form, of a long-incubated racism, both institutional and incidental – a casual, acceptable prejudice. Such racism doesn't emanate, as some have argued, from the Jewish component of Israeli nationhood. It is informed by the Eurocentric cornerstones of the country: the belief, expressed by Israel's founding fathers and still current, that the nation should be a bastion of the "enlightened" west in the heart of the supposedly savage Middle East. As well as underpinning regional policy, such prejudice has long been directed at Israel's Jews of Middle Eastern origin, rubbishing their culture and turning them into a socioeconomically stunted group.

Racism is the byproduct of the isolationism that is Israel's preferred form of regional interaction – it is the sniffy neighbour of the Middle East. The ban on travel to most Arab countries is of no consequence to the majority of Israelis, who could not be less interested in the region. That's also why practically nobody bothers to learn Arabic, one of Israel's official languages: there is no perceived benefit in communication with the people of the locale. This vacuum-sealed lack of curiosity is the perfect breeding ground for prejudice, because a minimal interest in variety is the precursor of tolerance and because cultures grow myopic without exposure to outside influence.

Such a disdainful refusal to be part of the region is nonsensical, given that Israel's majority population is of Middle Eastern origin and that Judaism is so acculturated to the Arab world. But Israel has severed itself from a long-valued Judeo-Arab heritage, preferring to present a European image. Now, parading intolerance as a prized national feature has made Israel intolerable to anyone who fits the ever-widening definition of "other" – and the country is an increasingly insulting irritation to the region it has so arrogantly snubbed.

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