Over 100 days of war and counting. The news from David Cameron's high-altitude attempt to pick winners in Libya's civil war is gloomy for those who believed, back on day one, that a quick win in the north African desert was going to rehabilitate the damaged doctrine of "liberal interventionism".

The heads of the air force and the navy have announced that their services can't carry on combat for much longer without more kit, and that's even before Liam Fox's latest cuts announcement.

The secretary-general of the Arab League, Amr Moussa, has found what Tony Blair never had – a reverse gear – and changed his mind about endorsing the attack, removing the fig leaf of regional support which Cameron made much of at the outset. Arab involvement was always on the cool side of unenthusiastic, and its propaganda utility was reduced because it came from regimes with no better mandates to rule than Muammar Gaddafi. Now this looks ever more clearly like another straightforward war by former colonial powers against an Arab nation.

The cost which the allegedly cash-strapped government has found to keep the operation going has hit £260m already, despite George Osborne's early pledge that it would be "tens of millions, not hundreds of millions, of pounds", and is rising fast.

Opinion polling shows little support in the combatant countries for continuing, and still less for escalating through either bombing non-military targets or the deployment of regular ground forces (the irregulars already being there, we can assume).

The Italian government has had enough fighting and has joined the ceasefire chorus. More surprisingly, Republicans in the United States have tried to declare the war unlawful and are demanding American disengagement – far from true to type. And civilians are increasingly victims of Nato's bombing raids. Even the bombers owned up to nine such deaths last week. In other recent wars, civilian fatalities could be euphemistically filed under "collateral damage", since keeping ordinary folk alive was not the official purpose of the conflict.

Since, however, "protecting civilians" is the rubric under which this whole bill of goods was marketed, such casualties in Libya confound the whole project and leave David Cameron open to the charge of hypocrisy, to say the least.

Meanwhile on the ground, neither party to the civil war, neither Tripoli nor Benghazi, Gaddafi nor his opponents, seem within sight of the decisive blow.

So the Libyan war is now short of cash, munitions, allies, sponsors, support and purpose. Benghazi leaders talk optimistically of a resolution by August, although this seems to lean more on religious timing – the start of Ramadan – than military realities. Time, one might have thought, for a ceasefire and talks towards negotiated political solution acceptable to the Libyan people themselves.

That is the view of the African Union, China, Russia, India and Turkey – to name just a few of those states urging an end to hostilities. That is now mainstream world opinion. It is also, intermittently at least, the view of Colonel Gaddafi himself, who has embraced ceasefire proposals that London and Paris have brushed aside.

Now under the shadow of an international criminal court arrest warrant, issued yesterday, it should at least be possible to induce Gaddafi to agree to serious talks on Libya's political future. As for the Benghazi regime, it could scarcely say no, given its evident dependence on Nato firepower.

But a ceasefire only runs up against the combatants' clear aim – to save face for Cameron. Him, and Nicolas Sarkozy. Having started on the basis of what is now clear was a grotesque misapprehension of the actual situation in Libya, they nevertheless demand victory before finishing. This position is supported by David Owen and few others, for whom maintaining the credibility of Nato in the world trumps all other considerations.

The definition of winning the war in Libya at present pivots on Gaddafi doing what the royal family of Bahrain – to take one pertinent example – has declined to do, and stand aside.

Even if that were to happen it is entirely unclear what the next step would be in a deeply divided country. Cameron could be doomed to re-run the catastrophe of Iraq, seizing control of an Arab country by main force and with no clue as to how or by whom it should be governed thereafter.

In fact the governments of the west should by this time be more used to losing, or at least not meeting the objectives set when the conflicts of this century began. Neither Iraq nor Afghanistan have been "won", nor will they ever be.

That is because these wars are all marked by imperial political overstretch – they are the living, if that is the right word, expression of the mentality that a few rich and powerful countries have the right to intervene where they will to further their own interests which, in the case of Libya, clearly include oil.

Most people in Britain want the bombing to end. They want no more wars of intervention, and they want the money saved. On that point, at least, the cabinet and the generals might be able to agree.