John Kerry, the US Secretary of State, has urged Kurdish leaders to stand with Baghdad in the face of a Sunni Arab revolt but the Kurds appear to have concluded that Iraq is finished as a unitary state.

On the battlefront, the attacks of the Islamic State of Iraq and the Levant (Isis) have slowed but government forces do not look as if they can regain lost territory. “We are facing a new reality and a new Iraq,” said Kurdish President Masoud Barzani at the start of his meeting with Mr Kerry in Iraqi Kurdistan. Earlier, he had blamed “the wrong policies” of Prime Minister Nuri al-Maliki’s for the violence and called for him to go, saying it was “very difficult” to imagine Iraq staying together.

The Kurds used the opportunity presented by the Isis assault and the disintegration of the Iraqi army in northern Iraq to take over territories disputed with the Arabs in Kirkuk, Nineveh, Salahuddin and Diyala provinces. This is a broad swath of land which is either populated by Kurds or from which Kurds say they were ethnically cleansed by Saddam Hussein and his predecessors. This includes the oilfields of Kirkuk and newly discovered oil or gas fields.

Mr Barzani is in a strong position because his Peshmerga soldiers are the most coherent military force in Iraq as the Iraqi army fails to stop Isis and its allies. It is clear that Isis is not treating the Peshmerga as its main enemy at the moment; though there have been clashes here populations are mixed along what used to be called the “trigger line” running from east of Baghdad on the Iranian frontier to the north-east corner of Syria. The battle for self-determination by the Iraqi Kurds seems close to being won as the Iraqi state founders and is in no position to prevent Kurdish independence. In an interview with CNN, Mr Barzani repeated a threat to hold a referendum on independence, saying it was time for Kurds to decide their own fate.

It is unlikely that Baghdad will in future control much in the Sunni provinces, though its security forces are still fighting to hold part of Baiji refinery after receiving reinforcements by air. Militants launched an attack on one of the government’s largest air bases, known to the Americans as “Camp Anaconda”, less than 65 miles from the capital. The UN says that 1,065 Iraqis were killed in June, but admits that the real figure may be much higher.

ORDER IT NOW

Military changes on the ground are outpacing Mr Kerry’s attempt to coax into being a new Iraqi government without Mr Maliki and led by people who can reunite the country. But the moment when this could be done may have already have passed since Baghdad no longer rules much of Iraq to the north and west of the capital. Its national army of 350,000 soldiers is demonstrably not prepared to fight for Iraq as a nation state. The reliance of Mr Maliki on purely Shia militias emphasises that the rump of the Iraqi state can only be defended by sectarian forces – even though Grand Ayatollah Ali al-Sistani and the Shia leader Muqtada al-Sadr have denied that there is a Shia levée en masse.

For the moment, the Iranians do not want Mr Maliki to be removed on the grounds that this is an American attempt to replace a pro-Iranian prime minister with a pro-American one. The Kurds will probably go a certain distance to accommodate the US. “If they decide to withdraw from the Baghdad political process it will accelerate a lot of the negative trends,” said a senior State Department official.

Mr Kerry said Iraqi leaders must “produce the broad-based, inclusive government that all the Iraqis … are demanding”. But the Kurds, Sunni and Shia of Iraq appear to be fast going their different ways.