Maurice Saatchi has a strangely hypnotic way of making presentations. He uses PowerPoint better than anyone I've come across. He builds up his logic slide by slide, sometimes taking you to a conclusion you don't agree with by way of a series of arguments it is impossible seriously to contest.

I still remember the first time I attended one. It was in 1995, in the days before Tory presentations moved from PowerPoint to Out of Power-point. Lord Saatchi explained the Conservative problem this way. Labour was seen as kind but inefficient (mouse click, new slide), while the Conservatives were seen as cruel but efficient. Now (mouse click, new slide) Labour was trying hard to be seen as efficient (mouse click, new slide) while the Tories were left seeming cruel but inefficient.

Cruel but inefficient, as Maurice pointed out, did not make a great advertising slogan. But it is a pretty good summary of the party's public image in 1997. And it also frames an argument that is still going on in the party and among commentators. Should the Tory party seek to return to the days when it was seen as cruel but efficient? After all it stayed in power for 18 years like that. Or should it try to be seen as kind but efficient? Tony Blair won massive landslide victories presenting himself in this way.

Every time that Gordon Brown's opinion rating rises triumphantly from calamitous fiasco to mere total disaster, there is renewed debate in the Tory party about the correct strategic choice. David Cameron's critics argue that the “heir to Blair” idea is desperately out of date. The electorate want gruffness. Voters distrust easy charm. They know that things are going to be tough, and desire that the Tories should appear to them once more as hard, businesslike and, well, cruel but efficient.

I disagree. In fact, I find it hard to believe this argument is still going on. I find it hard to believe that a group of people might be standing around wondering if not being nice is a good political strategy.

To start with, the idea that the electorate does not want charm is eccentric. When my colleague Matthew Parris tapped into his column the idea that “leaden charmlessness” was now Gordon Brown's “strongest selling point with the voters”, I wonder if he watched the cursor blink a while, reflecting on whether this could possibly be true, before incautiously clicking save.

I also think the advice that the Tories should be darker, angrier, more austere fails to understand what voters will want from them at the next election. Mr Brown's best card (not more, I reckon, than a seven of clubs) is that he represents safety, caution. It is better the devil you know. And the Tories? They need to offer hope, optimism, sunshine, light at the end of the tunnel.

There are some, of course, who argue that this battle is over. The Tories have “decontaminated the brand” already. They may not be seen as “kind” but they are “kind enough”. There are plenty of Tories who feel that way, but I am afraid this is smug. The electorate still thinks the party is harsh and represents “them” rather than “us”. This remains one of the party's biggest weakness with voters, as polling repeatedly attests.

However, my primary reason for arguing that the Conservatives should adopt an optimistic, kinder, gentler tone does not concern political strategy. I have, in fact, a rather old-fashioned motivation. It is that I believe this tone to be right.

The Conservative got the big questions of the 1980s right. And getting them right made Margaret Thatcher a great Prime Minister. I did not think at the time, however, and I do not think now, that the party's tone was admirable. Albeit that the Tories faced hard battles against unyielding opponents, I think they were often unnecessarily strident, sometimes hubristic, and could seem uncaring.

The next government - whether Conservative or not - will face very hard decisions about public spending. It will have to reduce some services, refuse pleas for assistance, make redundancies, turn down worthwhile new ideas. Some people will be hurt who have done little or nothing to deserve being hurt. It is hard to see what accompanying these tough calls with a harsh demeanour will achieve.

But getting the tone right is not merely about being civilised and sympathetic. It is central to Tory policy towards the State.

One of David Cameron's constant refrains is that he believes in a stronger society, but not a stronger State. This is often dismissed as meaningless, but is, in fact, the opposite. It is a big idea, but very hard to implement.

When Maurice Saatchi made his presentation on the “cruel but inefficient” Tories, a member of his staff was sitting next to him making sure the slides all worked. Fourteen years later and Steve Hilton is Mr Cameron's chief strategist. He spent most of the intervening years as a consultant, selling businesses the idea that capitalism and social responsibility - kindness and efficiency - can mix. When he puts those words about a stronger society into a Cameron speech they represent to him a real intellectual argument, and not a political slogan.

His thought is that the bully pulpit of the premiership, and its tools of influence, can be used to encourage individuals to behave better to each other. In place of much state coercion and regulation, there will be a stronger society based on voluntary initiative. This is an ambitious idea at the best of times, but will be severely tested in a harsh economic climate. But it cannot work at all without the right prime ministerial leadership. It needs Mr Cameron to be gentle, socially concerned, caring. Kind and efficient become essential partners, rather than political choices.

A harsher Tory party? Mouse click, next slide.

daniel.finkelstein@thetimes.co.uk

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