There’s been a lot of hysterical reaction to I.S.I.S.’s big land-grab in Central Iraq over the last two weeks. But there’s some wonderful bad news—“bad” from I.S.I.S’s perspective -- in the fact that all their gains have been on the very flat, dry plains of Central Iraq. The Northern pincer of their big advance, which was supposed to swing north through Tal Afar, has stalled badly.

And for that small mercy, I give wholehearted thanks to whatever god may be. Although god or gods had very little to do with it. The heroes of this story are the Pesh Merga, the very cool Kurdish militia; and topography. Bless the hills of Kurdistan! I always loved them, especially in Spring when the flowers explode over their slopes. But now those hills and the men and women of the Pesh Merga—the Middle East’s only truly gender-neutral fighting force—are the only thing saving all the terrified, dwindling minority communities of Northern Iraq from the savagery—yeah, savagery; why lie?—of a new zombie generation of Wahhabized Arab/Sunni jihadis.

What the jihadis have accomplished is grim enough, but their showoff videos of beheadings and mass executions are minor surges in what is, like it or not, a rational process: The partition of Iraq into three, rather than the previous two, ethnic/sectarian enclaves. Before I.S.I.S made its big move, Iraq was an unstable, immiscible column divided into Kurdistan and “everything else,” with “everything else” ruled by a weak Shia army.

Now the natural three-term partition is in place again, with the Sunni of the center, Saddam’s tribe, back to doing what they do best. I don’t mean to minimize the brutality of the operation, but this is a fairly bloody part of the world, and we contributed rather significantly to that blood-mush ourselves.

As long as the Sunni jihadis focus their revenge on fellow Sunni Arabs, their truly scary potential for pogroms is limited. What I truly fear, as a fond former resident of Iraqi Kurdistan, is that these creeps should break through to the North, into the hills where what’s left of Iraq’s slaughtered minorities have found a temporary haven. But so far, they’ve failed to do that at all. All their gains have come among their fellow Sunni on the Central Plains, which has muted their bloodlust somewhat. If those jerks ever got loose among the Assyrian, or Yazidi, or Turcoman, or Chaldean, or Kurdish communities hiding in the hills…well, you don’t have to guess about what would happen. They’ve said very clearly what they’d do, and they’ve done it often enough that there’s no reason to doubt their word.

So thank you, plate tectonics, for pushing up the hills along the northwestern borders. Thank you for diverting the Sunni jihadis away from the “kuffar” unbelievers whom they'd would kill with even greater enthusiasm than they show on their own.

Actually, topography has everything to do with what’s gone well or badly for I.S.I.S. in this latest push. If you know the ethnic makeup of the turf they’ve taken, their “shocking gains” don’t seem so shocking, or impressive. After all, we’re talking about a mobile force--mounted on the beloved Toyota Hilux pickup truck, favorite vehicle of every male in the Middle East—advancing over totally flat, dry ground in pursuit of a totally demoralized opponent. In that situation, any force could take a lot of country very quickly. It’s just a matter of putting your foot on the accelerator, moving unopposed on the long stretches of flat desert, then dismounting at the next crossroads town for a small, quick firefight against a few defenders who didn’t get the memo to flee. Once they’re dead, you floor it again until the next little desert town.

So this isn’t the second coming of Erwin Rommel by any means. Everything has conspired to push the Sunni advance, from the lousy opponent they’re up against to the terrain, which is a light mechanized commander’s dream.

Flat and dry is how a mechanized force commander wants his ground—and believe me, you haven’t seen flat and dry until you get to Iraq. Once you’re south of the Kurdish mountains, you’re on a dried mudflat. Iraq is much flatter than the deserts of the US, most of which get much more rain than central Iraq. No rain means little erosion, with few wadis or ravines to slow those Toyotas down. This is, after all, Mesopotamia, a land literally built by the sediment of the Euphrates and Tigris. It’s river mud, but nice and dry because very little rain falls, especially in June (average rainfall in June is 5 mm, the size of the numbers printed on an ATM card).

On ground like that, any force with good morale and enough fuel could advance as quickly as the Sunni have. It’s the Bonneville Salt Flats of insurgency, the place you go to set new speed records.

But in the North? No world records set there. In fact, I.S.I.S. seems to be bogging down badly around Kirkuk. To understand why, you need to consider both ethnography and terrain. And in fact, those two things are linked very tightly here, for some grim historical reasons. If you look at an ethnic map of Northern Iraq, you’ll notice that the minority sects and ethnic groups (those two categories tend to run together in the Middle East) are clustered north of the Central Iraqi plain, where the ground rises toward the serious mountains along the Turkish and Iranian borders.

There’s a reason for that, a simple and cruel one: Minority communities that aren’t protected by the hills tend to get wiped out. All over the world, you’ll find groups described as “hill tribes,” and in almost every case, if you go back a few centuries you’ll find that these aren’t “hill tribes” by choice, but defeated tribes who were forced off the plains and into the hills to survive. In places as far apart as Burma and Kurdistan, that pattern holds very clearly.

The hills of Northern Iraq hold what’s left of some extraordinary, beautiful cultures that have been wiped out in the more accessible parts of the country. And unfortunately, Sunni bigots have been ramping up their efforts to kill the survivors of these groups even in their remote hill towns.

The strangest of all these minorities have to be the Yazidi. When I was living in Kurdistan a few years ago, even the Americans bought into the prevailing Sunni slanders about Yazidis. I remember one Southern gentleman who’d come back from a weekend visit to Sinjar, a Yazidi town near the Syrian border, saying, “They really are devil worshipers! A snake cult!” Of course that dude was a product of Augusta, Georgia, and played golf—far gone, in other words. Not much you can do with someone wrong-headed enough to play golf.

The Kurds, who’d come through a nightmare century with remarkably little hatred for anyone, as far as I could see, didn’t buy this at all. My Kurdish students, as fine a group of people as I’ve ever met, used to say at every opportunity, “I have Christian friends! I have Yazidi friends! I have Turcoman friends! I have Shia friends!”

I guess if you’re a middle-class American, “I have [minority-sect] friends” sounds sort of patronizing. At least, when I told people back home about my students’ boast of inter-community friendships, the kewl leftists among them sneered a little, like “Oh that’s just like whites saying ‘my black friends.’”

Which, frankly, made me want to break a latte glass over their heads and cut their throats with the broken base. No, it isn’t like that slack Berkeley cliché about “my black friends”; it isn’t like that at all. I just wish Americans would stop assuming every place is like us. Let me tell you, for a Sunni Kurd to say, “I have Shia friends, I have Christian friends” is about as brave and radical as it gets, short of suicide, in the Middle East. I never heard any of my Saudi students say anything remotely like it. Well, how could they? By law, Shi’ism and Christianity are banned in the Kingdom. So they didn’t have the opportunity, even if they’d had the mindset (which they didn’t).

Something wonderful came out of the horrors of 20th century Iraq, among the Kurds of the Northern hills. They became the only non-sectarian population in Iraq, and perhaps the only such group between Lebanon and India.

All the hill peoples, the few who’d survived Sunni pogroms, were kind to each other. When violence came into the hills, it came from the plains to the South.

All the vulnerable minorities in the Northern hills had been hit by waves of violence from the Sunni majority to the south: the few remaining Assyrian Christians who held out in little mountain towns like Zakho, a pitiful remnant of the genocides perpetrated against them by the Ottomans, and then by Sunni militias in the 1930s; The Turcoman, who are Sunni but Turkish-speaking—in other words, not Arab—and don’t you ever doubt that Arab chauvinism has a HUGE part in what passes for Sunni jihadism. The Turcoman are the third-biggest ethnic group in the country, and because they’re non-Arabs, often Shi’ites, and just plain “visible minority,” have been subjected to pogroms, discrimination, and mass murder for generations.

The Turcoman towns are in a particularly dangerous position, on the plains at the foot of the northern hills. They’ve been taking a lot of casualties fighting off the northern prong of the Sunni advance. Tal Afar, the most important Turcoman town in the North, seems to have fallen to the I.S.I.S. as of June 23, 2014, though it’s always a good idea to wait a day or two before believing any wartime claim about cities lost or gained.

What makes it easy to believe Tal Afar has fallen is topography. I.S.I.S. is a mobile force, fast and light. Anything on the plain is vulnerable to it at this point, and Tal Afar, unfortunately, is a lowland town, with an official altitude of about 1300 feet/400 meters.

The biggest and strongest of the hill tribes, the Iraqi Kurds, are a little safer. Not only do they have the best fighting force in Iraq in the Pesh Merga, but they are safe behind a wall of high hills. The big Kurdish cities, Erbil and Suleimaniya (my beloved home in 2009-10), are safe behind high hills, far from the Sunni plain. Suleimaniya has an official altitude of about 2900 feet/900 meters, and the hills that surround the city are much higher, with Halgurd, Iraqi Kurdistan’s highest point, reaching 12,000 feet. Terrible, terrible ground for a light, mobile attacker like I.S.I.S—thank god, or tectonics, or whatever.

Of all the hill tribes, the Sunni Kurds are doing best in this chaos. It’s allowed them to take Kirkuk, which they always needed and wanted, and it also just so happens to put the one and only “supergiant” oilfield in the North (5 billion gallons) totally inside Kurdish territory.

I’m happy as Hell for the Kurds. I love them anyway, and miss Suli a lot—but more than that, it’s simple justice that they get a break for once. The Kurds have paid their dues. Saddam’s murderers in uniform killed nearly 200,000 Kurds, and the man from Tikrit was supposedly very disappointed he hadn’t been able to wipe them out completely.

At the moment, I.S.I.S isn’t even trying to pick a fight with the Pesh Merga—a fight they would lose very quickly if it ever did happen. But then Sunni jihadis have always liked softer targets, the softer the better.

Which is why what jihadis like most of all is to kill the Yazidi, the most helpless and vulnerable of all the hill peoples.

The Yazidi are one of the saddest stories in a region full of stories too awful to remember if you want to keep your sanity. These poor, remote mountain people just want to be left alone. They’ve never attacked anyone. They trace cool, weird serpent designs on their beautiful white temples, practice clan-marriage (endogamy), but then so do most Sunni Iraqis; it’s normal to marry a first cousin here, and it’s normal not to like the person you marry much. Affection is focused on siblings, offspring, and cousins; “A spouse,” as the old Irish joke has it, “is only a relative by marriage, after all.” That wouldn’t be a punchline here, just a fact.

So the Yazidi actually share a lot of traits with the Sunni majority. They’re no threat to anyone; 70% of them live in poverty, preferring quiet deprivation to the risks of testing Sunni tolerance. But even that isolation and humility wasn’t enough to save them from the new generation of Wahhabized Sunni growing up on the plains.

The problem was terrain. Sinjar, unfortunately, is only at the edge of the sheltering hills. It’s about 20 km east of the Syrian border, on mostly level ground—easy ground for jihadis in those white Toyota pickups—and, worst of all, due west of Mosul, which has always been a nasty hole full of haters, pogrom specialists. The Kurds of Suleimaniyah would only drive to Kirkuk in the daytime—as for Mosul, they wouldn’t go there at all, ever.

To the sort of haters recruited by I.S.I.S., the Yazidi of Sinjar were offending God just by existing. So, way back in 2007, before most news-consumers had even heard of the group, four I.S.I.S recruits, typical young males from the new generation of fanatical bigots, drove four trucks filled with explosives into the center of Sinjar and blew them up. 454 Yazidi were killed, another 500 seriously hurt.

A thousand people killed or maimed in a few seconds. The population of Sinjar is only 23,000—the Yazidi have been slaughtered and terrorized for generations, and there aren’t many of them left in the first place. The Ottoman Turks added the Yazidi to their list of genocides, killing most of them in the last years of the Empire—a going-away present if you like, or a prelude to what Ataturk was going to do to the Anatolian Greeks a few years later.

So, by 2007, the Yazidi hardly existed as a people. But they were still worth slaughtering, if you’re a Wahhabized Sunni madrassa zombie.

In a few seconds, four of those products let go of their dead-man switches and killed a full 5% of the remaining population of Sinjar. And that wasn’t the only atrocity visited on the Yazidi; they were pulled off buses and shot ‘til the clips were empty, to shouts of “Allahu Akbar."

Ah, I shouldn’t get upset. Doesn’t pay. What’s ironic, though, is that some of the comments on my last Pando article about I.S.I.S accused me of writing “love note to terrorist monsters”—being too soft on I.S.I.S, in other words. God, if that sanctimonious idiot only knew! You haven’t even begun to feel the terror of Sunni pogrom until you’ve had a very literate, intelligent Pakistani colleague dismiss the killings of Shahbazz Bhatti and Salman Taseer with a shrug, a smile, and the casual observation: “They were kuffar, and they deserved to die."

Have somebody you respect tell you that in one of the most remote towns in the world, where you happen to be one of a total of seven “kuffar” in residence, and then see if you’re soft on Arab/Sunni chauvinism.

I know, better than most of you, what Sunni jihad means. I don’t take it lightly. But I’m trying to get the story right, and that means keeping the ol’ fear and loathing to a minimum, unlike all the other sanctimonious, hysterical reporters acting like I.S.I.S. is a hybrid of Rommel and Subotai.

It’s not. It’s a middling-size, middling-skilled militia, and if we have sense to let it bubble and squabble with other Sunni militias down on the plain, it will devour itself, as it already shows signs of doing, now that fighting has started between Ba’athist/Sufi militias and I.S.I.S in the Sunni suburbs to the southwest of Kirkuk.

Let I.S.I.S bleed in those turf wars, down on the plain, its natural territory. And if it’s ever stupid enough to attack the Kurds in the hills, then may it be nicely and thoroughly smashed on those rocky hills—plate tectonics and/or God willing.

[illustration by Brad Jonas for Pando]