The murder of the American ambassador, Christopher Stevens, and three of his staff in Benghazi in retaliation for a US-made video slandering the Prophet Mohammed will have serious repercussions in the US weeks before the presidential election. The killings undercut President Obama’s claim that the killing of Osama bin Laden has been a death blow to Jihadi Islam. It will also make less credible the White House’s suggestion that it played Libya just right, staying in the background but helping end the rule of Col Muammar Gaddafi.

Anything that reminds American voters of 9/11 has serious political implications. Deaths of American soldiers in Afghanistan no longer have the impact they once did. But there is something shocking and new about the death of Mr Stevens, the first American ambassador to be killed anywhere in the world since 1979, which will give a jolt to opinion across the world.

The Libyan revolution was never quite as it was portrayed by the media, politicians and diplomats at the time. It is true that its leaders in Benghazi were astute enough from the beginning to play down the role of Islamic militants in the uprising which began on 15 February 2011. They had no wish to frighten Western opinion when they were angling for military support from Nato which they were to receive the following month as Gaddafi's tanks advanced on Benghazi.

The truth is that the Arab Spring uprisings, not just in Libya but across the Arab world, drew much of their explosive strength from the combination of very different people and strands of opinion united by hatred of oppressive and corrupt autocracies. Muslim Brothers, middle class intellectuals, Jihadi Islamists, well-off businessmen, impoverished farmers and a medley of others stood together and in Tunisia, Libya and Egypt succeeded in overthrowing long-established dictatorships.

But the opposition to Gaddafi in the 1990s and after had always been primarily religious, strongest in Cyrenaica, eastern Libya. But if people were anti-Gaddafi at that moment they were also against the US occupation of Iraq. East Libyan towns provided a disproportionately high number of suicide bombers who went to Iraq.

It is not surprising that some, at least in Benghazi, should have reacted with extreme violence to reports of a video made in America mocking the prophet. Libyans named their uprising the 17th February Revolution for a reason. The first demonstrations were called for 17th February 2011 to commemorate an event five years earlier on 17 February 2006 when crowds assembled in Benghazi outside the Italian consulate to protest against an Italian minister wearing a T shirt showing offensive Danish cartoons of the Prophet Mohammed. Gaddafi’s security services opened fire and at least 10 demonstrators were killed and many more wounded.

Do the Libyan killings and the over-running of part of the US embassy in Cairo on the same night mean that extreme Islamists were always waiting to spring into violent action once the powers-that-be were overthrown?

This would be a misunderstanding which springs in part from the over-simple and propagandist media coverage of the Libyan rebels during their uprising in 2011. They were presented as white hats and Gaddafi’s forces as black hats, while journalists, and particularly TV channels, uncritically broadcast reports that government troops were involved in mass rape. When such tales of atrocities were discredited by Amnesty International, they were ignored.

In reality, the rebels were always more violent and anarchic than was reported. They would hardly have lasted more than a few weeks against Gaddafi without close air support from Nato. Since the fall of Gaddafi many of these militias have turned into uncontrolled bands of thugs. It is not exactly that the revolutionaries of yesterday were always anti-American or anti-Western. It is rather that the revolutionary explosion of last year followed waves of protests by what politicians, journalists and diplomats once referred to contemptuously as the Arab Street. They protested ineffectively against their rulers supporting the US war with Iraq in 1991 and again in 2003. They marched in support of the Palestinian Intifadas in 1987 and 2000. They denounced the Israeli bombardment of Lebanon in 2006 and Gaza in 2008. For decades Arab rulers almost instinctively took pro-Western positions in opposition to the wishes of their own people.

From the beginning of the Arab Spring demonstrators were clear that they would not countenance the degree of foreign intervention to which their rulers had previously bowed. This was true in Egypt, but it also resonated in Libya despite the victory of the insurgents entirely depending on foreign intervention.

There are still plenty of people in Western armies and intelligence services who feel nostalgia for the old way of doing things, when they dealt with a compliant Egyptian army and did not have to worry about democratically elected Muslim Brothers or others more extreme. The Arab Spring was never a collective vote in favour of Western states, but a series of real revolutions that have other good and nasty surprises in store.

p.cockburn@independent.co.uk