Few who lived through the exciting but stricken decade that was the 1980s would want a re-run. Margaret Thatcher was a woman of and for her time. Besides, Britain has become an even more secular country over the past quarter of a century, and would be likely to be even less receptive now than it was then to arguments grounded in Christian belief. But for all that, reading God and Mrs Thatcher I felt the painful absence of a moral dimension to our modern politics. And I was struck again and again by how serious a thinker Margaret Thatcher was. I found myself comparing her to her successors—to their disadvantage. Her detractors often claim she had a second-rate mind, but if she did it was one that most of them should be proud to possess.

Here, of course, I am shining a spotlight on David Cameron.  It is he who employs Lynton Crosby, and he who is ultimately responsible (with George Osborne at his elbow) for the depressingly narrow nature of the Tories’ campaign. Think of all the important issues that trouble many people which could be discussed but are considered either out of bounds or barely worth mentioning.

As I write, immigration is certainly one of them despite being at the top of voters’ concerns. This is very odd. There are almost no votes to be lost, and some to be won from prospective UKIP supporters, by raising the matter. I can see that Mr Cameron is embarrassed by his failure to bring down numbers to the “tens of thousands” as he promised in 2010; in the year to last September net migration was a record 298,000, of whom 190,000 came from outside the European Union. But most people can understand that it is not easy to stem the flow. What they generally look for, I think, is evidence of a balanced, decent but determined approach which shows that the Prime Minister really understands the disruptive effect of untrammelled immigration on people’s everyday lives.

Another virtual no-go area is defence. Mr Crosby is said to believe in his wisdom that there are no votes in it. Philip Hammond, the Foreign Secretary, was reported to have expressed the same view to Tory MPs at a recent private meeting. He denied he had, and then said in a speech that Britain faces the “greatest challenge” to its national security for decades. He was referring to the dangers of a resurgent Russia directed by an increasingly unpredictable and unstable Vladimir Putin, and to the rise of Islamist fanatics in the Middle-East and North Africa. If Mr Hammond is right, as I am sure he is, why are we not hearing more from the Tory front bench about these dangers, and why does Mr Cameron refuse to guarantee that already diminished levels of defence expenditure will be maintained? It requires moral courage to tell comfortable voters they are threatened,  and that more money may have to be found to protect them, but in the end most people will respect such candour.

Perhaps the most serious failing is the absence of any discussion about the “broken society”. The phrase was used by Mr Cameron after the riots in August 2011 but seems not to feature on Mr Crosby’s famous “grid” of policy announcements. Our sick society certainly hasn’t been mended. Almost every week yields more appalling details of children in Oxford, Sheffield, Rochdale or other places being abandoned by the authorities to their tormentors. In most cases such abuse was well underway in the Labour years, so the Tories need not feel politically vulnerable were they to address it. Where is the heart in their campaign? Where is the concern for hard-pressed families (marriage has received only minuscule tax breaks in the teeth of Lib Dem opposition) and for the problems they face—from hardcore pornography corrupting young minds to the allure of drugs? How lethally far removed the Tory hierarchy often seems during this election campaign from the experiences of ordinary people.