The phrase "second resolution", with its echoes of the pre-Iraq diplomatic wrangling of 2003, strikes an ominous note. The French call for UN authorisation of regime change is, at best, a rash gamble.

At worst, it will shatter the coalition, drive Britain in the direction of another catastrophic land war, and chip away at the pillars of legality on which this war was erected.

But the minimalists are no less confused. Those who advocate a narrow interpretation of UN Resolution 1973, as allowing only a no-fly zone and purely defensive measures, have no credible answer to the questions of how western forces will halt their military operations without risking a resumption of horrific attacks on civilians, or why the rebels would accept a de facto partition. It is therefore imperative that Nato degrade Gaddafi's war machine, because no settlement will be stable or enforceable without irreversible change in the balance of power.

Regime change as an ambition is neither imprudent nor unusual. This is the British position in, say, Myanmar and Iran. But as explicit policy, it is reckless, wishful, and devoid of strategic nuance

First, France could not get the resolution it hints at. Resolution 1973 barely escaped a Russian and Chinese veto. Only days ago, a meeting of the Bric countries condemned the use of force against Libya and called it all-but illegal. Every one of these four emerging powers is a member of the UN Security Council.

Second, Resolution 1973 was a triumph of international diplomacy. It combined Arab support, elastic language, and humanitarian objectives. Libya was everything Iraq was not. If western powers sought – and were denied – a second resolution, but pushed for regime change regardless, this triumph could be stillborn. Unilateral action would inflame Arab opinion, dissolve Turkish and German support, and generate an international chorus of condemnation.

The war in Iraq demonstrated that unilateralism has grave symbolic costs. The war in Afghanistan shows that a fractured and weary alliance is an ineffectual one. Repeating these two mistakes would leave Britain and France, in a few months' time, isolated from allies and their own parliaments.

Third, and most important, by what means does the coalition intend to topple Gaddafi? The two obvious answers – relying on the rebels, and an expansion in airstrikes – are unworkable.

Though the rebels will soon be flush with cash and arms, this will not swing the balance. They lack any meaningful organisation, training, doctrine, and cohesion.

The alternative to relying on the rebels as Nato's army is to turn Nato into the rebels' air force. In the 1999 Kosovo War, Milosevic's defiance forced Nato to target dual-use facilities such as bridges and power plants and, eventually, to begin concrete preparations for a ground campaign.

But emulating this model would be the height of folly. Targeting dual-use infrastructure in Libya would amplify the humanitarian crisis and would anger many otherwise supportive Libyans.

Above all, the prospect of ground forces should be viewed with alarm and scorn. In February, the US Defence Secretary, Robert Gates, argued that "any future Defence Secretary who advises the President to again send a big American land army into Asia or into the Middle East or Africa should have his head examined". There is wise counsel here for both Whitehall and the Quai d'Orsay: limited war demands limited aims.

The writer is an associate fellow of the Royal United Services Institute