Rebels, from the Wars of the Roses up to the present civil war in Libya, usually try to postpone splitting into factions and murdering each other until after they have seized power and are in full control. However deep their divisions, they keep them secret from the outside world.

Not so the Libyan rebels. Members of their Transitional National Council (TNC) in Benghazi last month detained their military leader, General Abdel Fatah Younes, on suspicion of treachery, lured him away from his bodyguards and murdered him. This week the head of the TNC, Mustafa Abdel Jalil, sacked his whole government on the grounds that some were complicit in the killing. He was apparently forced to do so in order to quell the rage of the powerful Obeidi tribe to which Younes belonged.

A ludicrous aspect of the whole affair is that at the very moment the rebel leaders are at each other's throats, they are being recognised by country after country as the legitimate government of Libya. This week TNC diplomats took over the Libyan embassies in London and Washington and are about to do so in Ottawa. In a masterpiece of mistiming, Britain recognised the rebel government on the day when some of its members were shooting their own commander-in-chief and burning his body.

If this is how the rebels behave today, when it is much in their interests to make a show of unity, how will they act once they are installed in power in Tripoli? But Nato's sole policy is to do just that. A UN Security Council resolution, intended to stop Gaddafi's tanks taking Benghazi for humanitarian reasons in March, transmuted rapidly into a bid to overthrow him. Britain and France, with essential backing from the US, still maintain that the good of the Libyan people requires the replacement of Gaddafi with those sturdy democrats from Benghazi and eastern Libya represented by the TNC.

Could a strategy of brute force work in a purely military sense? Could the rebel columns of pick-up trucks with machine-guns in the back advance to capture Tripoli behind a creeping barrage supplied by Nato firepower? The Libyan capital is increasingly short of fuel, consumer goods and electricity. The rebels have been making gains on the ground to the east and south-west of the capital. But even with the support of Nato air strikes the advance has been slow. If the rebels make such a meal of taking a town like Brega, with a population of 4,000, on the Gulf of Sirte, can they really fight their way into Tripoli with a population of 1.7 million?

Gaddafi may fall, but it looks increasingly that, if he does, it will be at the hands of a rag-tag collection of militias ever more dependent for success on being backed by tactical support from Nato aircraft. Given that the rebels lack a coherent leadership or a united military force, the outcome is unlikely to be a clear-cut victory. Even if victorious, the rebels will depend on foreign support at every level to exert authority over this vast country.

As with Afghanistan in 2001 and Iraq in 2003, the US and Britain found it was one thing to overthrow the Taliban or Saddam Hussein and quite another to replace them. Treating dubious local allies as the legitimate government has a propaganda value, but it is unwise to pretend that the local partner carries real authority. With this experience under its belt, it required real fecklessness for Britain to plunge into another conflict on the assumption that this time we were betting on a certain winner. Gaddafi may be overthrown but the struggle for power between internal factions is likely to continue.

Colourful, but woefully misleading

The foreign media had its failings in Iraq, was worse in Afghanistan but has reached its nadir in covering the war in Libya. Reporting has become largely militarised. Much of it is colourful stuff from the frontline about the dashes backwards and forwards of rebel militiamen. It takes courage to report this and reporters naturally empathise with the young men with whom they are sharing a trench. Their coverage tends to be wholly in favour of the rebels and in opposition to Gaddafi.

When Abdel Fatah Younes was murdered almost nobody in the foreign media had an explanation as to how or why it had happened. The rebel leadership, previously portrayed as a heroic band of brothers, turned out to be split by murderous rivalries and vendettas. Some reporters simply regurgitated the rebel authorities' unlikely claim that the general had been killed by pro-Gaddafi fighters with camps in Benghazi, while others mentioned that there were 30 different Islamic militias in the city.

To this day politicians justify Nato's intervention in Libya by citing atrocities supposedly carried out by pro-Gaddafi forces such as mass rape or extensive use of mercenaries. Human rights organisations such as Amnesty International and Human Rights Watch long ago revealed that there was no evidence for most of the atrocity stories, as did a UN commission headed by the distinguished legal scholar Cherif Bassiouni. These well-researched reports were almost entirely ignored by the media which first published the Gaddafi atrocity stories,

The militarisation of reporting in Iraq and Afghanistan was boosted by the system of "embedding" reporters with military units. This was inevitable to a degree given the danger from Iraqi insurgents or Taliban. But the outcome has been that war reporting has reverted to what it was during imperial skirmishes in the 19th century, with the world getting only a partial and often misleading account of what is happening in Libya.