By the beginning of 2012, it appeared that many parties in the Middle East were pulling back from a raw Sunni-Shiite, or even Sunni-everybody else, divide. The linchpin was Iraq. The Arab states, particularly in the Gulf, realized that a pure sectarian division in the Arab world would more or less cede Baghdad to Tehran’s influence. Iraq, for its part, gave clear indications that it had no intention of becoming a pawn of Iranian policy and wanted to become an integral part of the Arab world again. So a rapprochement of sorts was jerryrigged, an Arab League summit held in Baghdad, and the region seemed to be pulling back from the brink.

But recent months have more than reversed that correction. The return to a drift towards pure sectarianism is being largely driven by the war in Syria. The entire Sunni Arab world, ranging from moderate regimes to Al Qaeda affiliates, is united behind the opposition. The Alawite-dominated Assad regime, by contrast, has the strong support of almost all Shiite actors in the region, particularly Iran and Hezbollah. It’s estimated that several thousand Iranian and Hezbollah fighters are fighting in Syria on behalf of the Damascus dictatorship.

The sectarian division is also making itself overtly felt in Iraq for the first time in years. It’s no longer preposterous to imagine Iraqi national fragmentation along sectarian lines, as Sunni-Shiite tensions boil and bubble until they overflow the stew, and as Prime Minister Nouri Al-Maliki seems bent on establishing a new authoritarianism, if not an outright dictatorship. Iraq, too, is increasingly being drawn into the Syrian conflict. Maliki’s Iraq is now clearly part of the Shiite alliance supporting Bashar Assad. It’s allowing fighters from groups like the Abu Fadl Al-Abbas Brigade to enter Syria and join with Iranian and Hezbollah forces in defending key strategic positions for the Damascus regime. There is also considerable evidence that it is increasingly allowing matériel and supplies to cross its borders in aid of the Syrian regime.

But sectarianism hardly limited to the Syrian conflict. Intolerance, and indeed violence, against Coptic Christians in Egypt is greatly intensifying, particularly with the attack on the main Coptic Cathedral recently by thugs and government forces alike. Egyptian efforts at rapprochement with Iran have been stymied by bizarre and paranoid Salafist claims of Shiite proselytizing.

Sunni-Shiite tensions define the simmering but incendiary conflict in Bahrain, with regional forces lining up precisely along sectarian lines on both sides. The Shiite areas of the eastern governorate province of Saudi Arabia are witnessing unrest and repression, including the killing of protesters and the arrest of opposition leaders. Even what had been for a time a largely ideological divide in Lebanon is increasingly becoming—once again—more starkly sectarian in nature. The list goes on and on, almost without exception.

Those, like Marc Lynch, who argued during 2011 that “sectarianism was much worse in the 1990s” were obviously and completely mistaken then. I’d be amazed if anyone would be willing to repeat such an allegation in 2013. Like it or not, and against the better judgment of many, the entire region, and not just the Arab world, is dividing along strictly religious sectarian lines. Everywhere the emotional, cultural, political and literal barricades are up, pitting brother against brother, neighbor against neighbor and, most often, Muslim against Muslim.

It’s impossible to overstate the extent of the disaster this represents for the Middle East as a region. It means that most, if not all, regional actors are seeing the world largely through identitiarian and fundamentally irrational perspectives. Obviously the basis for some of the tension has to do with Sunni Arab and Turkish resistance to Iranian ambitions. But that hardly explains the depth or nature of the sectarian suspicions. Instead, it’s clear the region has entered into a period of paranoid groupthink based on fear and hatred of the religious other. But, of course, this “other” is most often anything but; it is actually friend, neighbor and countryman.

No other region of the world is currently giving itself over to such an advanced stage of neurotic hysteria posing as political analysis or strategy. Not only do the reforms promised by the Arab uprisings ring hollow in the context of rampant sectarian chauvinism, the whole region, and many countries in it, will be condemned to open-ended conflict, in many cases for no good reason whatsoever. Meanwhile most of the world will merrily move on, largely unencumbered by such all-encompassing prejudices and paranoia.