Churchill sacked two Chiefs of the Imperial General Staff before he found the man that he wanted, Sir Alan Brooke. What he respected most in Brooke, whose statue stands outside the Ministry of Defence with the words “Master of Strategy” on the plinth, was his moral courage: “I bang the table at him, and what does Brooke do? He bangs it even harder!”

Rumours that the Chief of General Staff, General Sir Richard Dannatt, will not be the next Chief of the Defence Staff (CDS) because of his outspokenness may prove premature, but they are dismaying nevertheless. Gordon Brown may be irked by the way that the media have seized on Dannatt's words, but the CGS has served the Government's security strategy more faithfully than he would have if he had kept his mouth firmly and self-servingly shut.

By calling for public shows of support for returning troops he has decoupled the issue of casualties and respect from the unpopularity of the Iraq war (and doubts about Afghanistan), taking much heat off the Prime Minister. His remarks soon after he was appointed two years ago - that we must not lose focus on handing over to the Iraqis, and quit the country as soon as possible - were at first construed as a policy attack.

In fact they were a reminder to other agencies what the policy actually was, for there was lethargy in parts of Whitehall. Dannatt saw with a clarity that is only now being admitted elsewhere in the MoD that there were not the resources to continue in Iraq and at the same time face the growing Taleban counter-offensive in Afghanistan.

Indeed, 18 months ago, Dannatt personally changed tactics in Helmand to reduce the surge in casualties. In all this, he materially diminished the antiwar rhetoric.

But if this “loyalty upwards” is unrecognised, Dannatt's “loyalty downwards” has also been misunderstood, as if he were some sort of shop steward for the Army.

It is far more subtle. “I want an army in five or ten years' time,” he said on taking over. From his previous appointment as commander-in-chief he knew that the Army was willing to fight, but that its capacity to endure, to keep going back on operations without losing edge, was less assured. Soldiers and officers were leaving in growing numbers. There were worrying cases of indiscipline, especially on operations - of which the death in custody of the Iraqi Baha Musa was the most public.

Soldiers know that senior officers fight their corner with the Treasury behind closed doors, but they were wondering just how hard they were fighting, and just how effectively. For example, cuts in the infantry's strength announced before Dannatt's appointment were appalling. The infantry bears the brunt of fighting, takes the greatest casualties: how could the MoD cut the number of infantrymen when fighting was only expected to increase?

The underfunding of infrastructure was evident to married and single soldiers alike during their increasingly short spells at home. Their pay compares unfavourably with civilian counterparts. And men were being killed every other day in Iraq or Afghanistan. Two years ago senior officers risked losing the confidence of their commands: the professional head of the Army had to signal his willingness to fight for the Army, whatever the personal cost.

It was straightforward leadership. But even in this Dannatt was circumspect, not directly criticising the MoD or the Treasury but calling instead for “a national debate” on what ought to be a reasonable level of spending on the Armed Forces. The positive public reaction should not so much shame the Government into finding more money for defence as enable it to do so.

In putting his head above the parapet, Dannatt was also doing a service to the man whose job it is to give the Government consolidated military advice, the CDS, Air Chief Marshal Sir Jock Stirrup. For the CDS to have exposed himself to political fire would have been perilous. That he did so in interview last week, admitting for the first time that the MoD's planning assumptions have been too long underfunded, that we cannot continue two simultaneous operations, shows how much Dannatt had been trying to avert a looming crisis for both the Army and the Government. This “top cover”, as Stirrup, a fighter pilot himself, might put it, is welcome, if a little late.

Strategy, however, is only one side of the CDS's remit, The other is shaping the defence programme to the ends of government policy - in particular matching equipment aspirations to the budget. As CGS, Dannatt, like the other single-service chiefs, is closely involved in this, but his influence in the biggest spending areas has been limited, and he has had to watch as the other two services have eaten into the budget. Eurofighter was planned years ago, while others such as the new aircraft carriers whose contracts were signed yesterday, were beyond his influence because they had Navy-RAF backing and brought political benefits in the shipyard constituencies. Projects such as these, with their above-average cost inflation, are squeezing the operational side of the defence budget as never before, and the Army takes the hit. Stirrup has said that the Forces “are stretched beyond the capabilities we have”. In other words, the determination of strategy has become a more-or-less incidental by-product of the procurement programme. That programme needs rebalancing and if Dannatt were to become CDS, his job would be to rebalance it.

I am not saying that a better “Master of Strategy” than Sir Richard Dannatt could not be found when the present CDS's term ends next year - only that I'd be amazed if one was. I would fear most, however, for the cause of moral courage in the Forces and the MoD if Dannatt were to be passed over for speaking out. Gordon Brown's proverbial clunking fist can no doubt make a noise as loud as Churchill's. But does he have Churchill's strength to square up to a thoroughly loyal if forthright officer, and the best man for the job?

Allan Mallinson is a military historian, novelist and a former cavalry officer

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