On 15 April, President Trump made an unexpected phone call to Khalifa Haftar, a Libyan military officer and former CIA asset who has launched an attack on Tripoli with the aim of overthrowing Libya’s nominal ruling authority, the UN-backed Government of National Accord. According to a White House statement, Trump ‘recognised Field Marshal Haftar’s significant role in fighting terrorism and securing Libya’s oil resources’, and the two men discussed their ‘shared vision for Libya’s transition’.

Only the week before Trump called him, the State Department had condemned Haftar’s assault on Tripoli as a dangerous escalation. The US has since joined Russia and France in blocking a UN Security Council censuring him. The GNA is embattled, a government in name only in a state without a state. But why is the White House supporting an obviously reckless act of aggression?

Parts of the story are becoming clear. Haftar visited Riyadh shortly before launching his assault on Tripoli, and the Saudis pledged generous financial backing. On 14 April, as his forces were struggling to advance, Haftar flew to Cairo for an audience with Trump’s favourite Middle East ally, Abdel Fattah el-Sisi. Trump made his intervention the following day.

Haftar’s forces have met resistance and not been able to reach the city centre. A friend in southern Tripoli told me he had moved his family out of the city. There have been air and artillery strikes on residential areas. The World Health Organisation estimates that at least 350 people have died.

Haftar has been amassing power in eastern and southern Libya for four years with the support of Egypt, the UAE and France. A putchist officer in Gaddafi’s 1969 coup, Haftar fell out of favour in 1987 during the ill conceived Toyota wars in Chad, where he was taken prisoner. Abandoned by Gaddafi, he was recruited by the CIA for its half-hearted effort to build a Libyan opposition and flown first to Zaire then Virginia. He seems to have lived there, on the CIA payroll, until 2011 when he cropped up in Benghazi during the uprising against Gaddafi. In February 2014, Haftar appeared on Libyan television, declaring another coup in the name of a Supreme Council of the Armed Forces (the name used by Egypt’s junta). In May 2014 he launched Operation Dignity, a campaign he has been fighting ever since.

Haftar’s forces are made up of the rump of Gaddafi’s gutted army, tribal militias and mercenaries. They call themselves the Libyan National Army. Human Rights Watch notes ‘a well-documented record of indiscriminate attacks on civilians’ and ‘summary executions of captured fighters’. Haftar has been clear about his intentions should he succeed in taking control of the country: military rule, in the Egyptian mode, with himself in charge.

Much of the mess in Libya is traceable to the Nato intervention in 2011, when the Western powers sought regime change under the cover of what Robert Gates would later called the ‘fiction’ that Nato forces were only disabling Gaddafi’s military command centres. Air strikes, British and French special forces, and an illegal circumvention of the UN arms embargo by the US helped to overthrow Gaddafi. There was little planning for what would come next. Just months earlier, Britain and France had been supplying the old regime with equipment designed for quelling rebellions, including ‘wall and door breaching projectile launchers’ and armoured crowd-control vehicles.

Haftar’s bid for Tripoli poses some odd questions. Why was it launched on the day the UN secretary general, Antonio Guterres, was visiting the city? Why didn’t Haftar secure the support of one of the major militias controlling Tripoli? And will Washington see it through to the end?