Two cheers this week for two generals (retd) and one field marshal (retd), and their joint letter to The Times. Two cheers for every brave soul (retd) who, from the sidelines, reviews the game in which they were once players, and voices the doubts that have long troubled them. To Field Marshal Lord Bramall and Generals Lord Ramsbotham and Sir Hugh Beach, and their letter about replacing the Trident missile system in yesterday's Times, in a moment.

Two cheers, too, for one Trade and Investment Minister (retd) who, after stepping down, has just described his civil servants as featherbedded and underemployed. If only Lord (Digby) Jones of Birmingham had said so at the time.

One cheer for President GeorgeW. Bush (retiring): honest at last about failures in his presidency and his judgment. But too late.

One cheer for Tony Blair (retd), who is reported this month to believe that his Government's decade of economic success was totally fortuitous. “It is true,” he told students at Yale, “that we had ten years of record growth when I was Prime Minister. I have, unfortunately, come to the conclusion that it was luck.”

Would that such candour had come to him sooner.

One cheer for David Miliband, the Foreign Secretary, who, now that his boss is courting a new president, has discovered (according to yesterday's Times) that the War on Terror was always a category mistake. “Terrorism is a deadly tactic,” he said this week, “not an institution or an ideology.”

But how much more useful it would have been for this intelligent and respected Labour MP (since 2001) to have added his support earlier to lonely critics of that view.

And no cheers at all to his brother, Ed, whose confessional memoir after Labour's coming defeat will admit that, as Secretary of State for Energy and Climate Change, he was devastated by the Government's decision in January 2009 to proceed with a third runway for Heathrow. It has not yet been written. It will be. Too late.

Always too late. But before continuing I must be fair to Lords Bramall and Ramsbotham, and Sir Hugh. Yesterday's letter to The Times was certainly not the first time that these retired military men have set out their opposition to the Trident replacement programme. They have been brave.

But their letter, written from the cover of retirement, is the visible part of an iceberg. Submerged, and still serving within the Armed Forces, are scores of silent experts and silent military leaders among whom the doubts expressed in the Times letter are widely shared, and have been for years.

I know that they should not speak publicly. What troubles me is the suspicion that discretion in public is accompanied by discretion in private, discretion to the point of gutlessness.

For courage rarely surfaces until retirement. Just how brave is our British habit of staying tight-lipped about unfolding policy calamities while still part of the policymaking team - and then, after a decent pause and a garnish of ermine, swinging about in the Upper Chamber with a “my Lords” here and a “my noble and learned friend” there, to pronounce on all the mistakes you apparently saw coming for years? How proud should a man or woman be of that?

There will always be disingenuous hindsight; but all too often the retired luminary is being honest when he says that he knew at the time a doomed policy was doomed.

I cannot believe that Ed Miliband is unaware of how unwise his Prime Minister and senior colleagues have been - both politically and in principle - to push Heathrow's third runway; or unaware that the project will go nowhere and be blamed later for heavy Labour losses in West London. Why should we wait for the Miliband memoir?

It sometimes seems that we all trudge down a long road we suspect is leading nowhere, nursing our private doubts and keeping our mouths tight shut. Who really believes that Barack Obama can turn America round? So why the elaborate ritual of affecting raised hopes and high excitement as his inauguration approaches?

Let those who think this brouhaha optimistic kindly raise their hands now. From the rest, would it be too much to ask for a vow of silence later? No “I told you so” please. You didn't.

Further self-denying ordinances, too, would be appreciated this January. When (probably this year) the Iraqi Government topples or slithers back into autocracy and sectarianism, would that section of media and political commentary that blows friendly or unfriendly to American intervention according to how many bombs have gone off in the previous week be so good as to avoid claiming that “it was always inevitable” that no proper democracy could be established there? If, like me, you do think that it's inevitable, say so now.

When (probably next year) America becomes horribly bogged down in Afghanistan, and we British can't make up our minds whether we can, or should, sneak away from the mess, could we please have a ceasefire on wise opinions that Afghanistan was always going to be a graveyard for Western hopes, and that it's a pity we got sucked in so deep in Helmand. If, like me, that's what you think, say so now. We could save a few soldiers' lives.

When Gordon Brown has lost the general election, and it emerges from diaries and media confessions by those no longer terrified of the man that he was from the start an appalling, raging, dithering, laptop-throwing typhoon of aggression, paranoia and insecurity, would those many in Westminster, Whitehall and Fleet Street who will soon be sharpening their quills to write that, of course, they knew it all along, please ask themselves why, in that case, they don't write it now?

When the decision is taken irreversibly to go for the nuclear generation of electricity in Britain in a really big way, could all those in the political and media class who are at present sitting on the fence, kindly admit their former indecision, and spare us their thoughts on how there was “never” going to be any other way for Britain to abide by our green commitments?

When the ludicrous Eurofighter project is finally admitted to have been misconceived since at least 1985; when a future government accepts that a national road-pricing scheme is the only way; when someone in authority spits out the truth that the scourge of drugs in prison is assisted by prison officers' connivance; when a Home Secretary confesses that the British police are bedevilled by crass incompetence, mismanagement and job creation; and when barristers are stripped of their wigs, the Post Office of its monopoly, offshore tax havens of their status, and House of Commons flunkeys of their tights... then this I beg all of you who will say (whether or not you know it yet) that you never doubted a thing must come to pass - say it now, before it does.

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