America’s Shia and Kurdish allies in Iraq turn on each other just as they are about to defeat the jihadists of Islamic State

THIS should be a time for rejoicing. The jihadists of Islamic State (IS), driven out of Mosul in Iraq in July, were defeated this week in their Syrian capital, Raqqa. Little remains of the “caliphate” but a few pockets and a bankrupt ideology. Alarmingly, the scramble for spoils is bringing forth old rivalries and new conflicts across the Fertile Crescent. One clash has come in Kirkuk, where explorers struck Iraq’s first oil gusher in 1927. The city is home to many groups, among them Kurds, Arabs and Turkomans. It lies outside the Kurds’ official autonomous enclave but had been held by them. On September 25th Kurdish leaders held a referendum on independence that included voters in Kirkuk. The affronted Iraqi government, led by Shia Arabs, ordered its forces to retake the city and other disputed lands on October 16th. They did so swiftly. Even with Kirkuk’s oil the Kurdish enclave is broke; without it, dreams of independence have been dashed (see article).

It is worrying enough that two American allies—the Kurdish Peshmerga and Iraqi forces—should turn their guns on each other. It is even more worrying that President Donald Trump has done little to stop them, declaring that: “We’re not taking sides.” Unless America fills the vacuum left by the demise of IS, Iran will do so instead.

The Kurds deserve much sympathy. Denied a state in the carve-up of the Middle East, and massacred with poison gas by Saddam Hussein, they consolidated their autonomous region after America toppled Saddam in 2003. When the Iraqi army collapsed before the IS onslaught in 2014, the Kurds fought back valiantly with Western help, and occupied Kirkuk.

Of late, though, Masoud Barzani, the Kurdish leader, has proved to be contemptuous of democracy (his mandate expired two years ago), and the fall in oil prices has bankrupted his government. His referendum was a reckless gamble to fend off dissatisfaction with his Kurdistan Democratic Party. Many Kurds, particularly in the other big faction, the Patriotic Union of Kurdistan, were wary. Iraq’s prime minister, Haider al-Abadi, demanded that the referendum result be reversed. Iran and Turkey joined him in squeezing the Kurds. America, the Kurds’ protector, opposed the referendum, and American-trained units helped recapture Kirkuk—to the fury of congressmen who believe the operation was orchestrated by Iran.

America has to step in to stop a new conflict in Iraq, between Shia Arabs and Kurds, taking root amid the rubble of the old one between Shia and Sunni Arabs. It will need great skill to help resolve the dispute over lands claimed by the governments in Erbil and Baghdad, and more broadly, to settle the question about how Iraq should be run. This will set a precedent for ending the war in Syria, determine the chances of jihadists returning and affect the regional power balance.

To a degree, America needs Mr Abadi to be a strong Iraqi nationalist, the better to resist Iranian influence. But an over-mighty government in Baghdad would risk repeating the oppression of the Saddam era. Iraq needs a decentralised state that gives its minorities safety, and a fair share of power and resources. A thriving Kurdistan is the first step.

America stands back

Mr Trump’s preference for bluster over complex diplomacy or, worse, “nation-building”, adds to the perils. On October 13th he pledged to confront “the rogue regime in Iran”, blaming Barack Obama’s nuclear deal for strengthening it. In fact, Iran derives its power mostly from the region’s chaos. Granted, confronting Iran on the ground is risky; it knows how to use proxy militias to bleed American troops. But Mr Trump’s blowhard talk risks provoking Iranian hardliners anyway. Right now, having done much to crush the jihadists in Iraq and Syria, America is letting Iran reshape the Arab world to its liking.