The murder of the American ambassador, J. Christopher Stevens, and three of his staff in Benghazi in retaliation for a US-made video slandering the Prophet Mohamed will have serious repercussions in the US weeks before the presidential election. The killings undercut President Obama's claim that the killing of bin Laden has been a death blow to Jihadi Islam.
Anything that reminds US voters of 9/11 has serious political implications. Deaths of 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 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 February 2011. In reality, the rebels were always more violent and anarchic than was reported. 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.
It is not exactly that the revolutionaries of yesterday were always anti-American or anti-Western. It is rather that, 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 surprises, both good and nasty, in store.