Both parties are tough-talking on the economy, school standards, welfare and crime. To be tough on crime, they want young people occupied in something useful.

The difference is that the Tory heart throbs with pride at the thought of teenage feet marching in shiny black leather, while Labour envisages them in trainers doing voluntary community work.

Conservative strategists are convinced that encouraging schools to start cadet forces - mysteriously floated after an off-the-record ministerial lunch - will be a winner, both with their own supporters and young people. The Tory High Command is so enamoured with the idea that it may be put into operation even before the election. “People who join the cadets can learn to operate radar, fly planes and other such things. We hope we can somehow target those youngsters and channel them in a particular direction. It’s all very well the Blunketts of this world saying they should do community service, but they’re not going to. You can’t get them into old people’s homes but you can get them orienteering and teach them how to use radar equipment and signals and that would be a thoroughly good thing,” one insider said briskly.

Not only would the plan appease those who mourn the passing of national service, but there is some suggestion that catching ‘em young might offset the current recruitment problems of the Forces.

But there are many detractors. Loyal Tories point out that the cadet leak should safely be regarded only as an early shot in the election silly season, although the Prime Minister’s political instinct on such things is regarded as sound.

New Labour, anxious not to rule out wrapping itsel.f in the flag, has so far only attacked the cost of the scheme, estimated at a headline-grabbing Pounds 1.5 billion. Others were left to worry about allowing teenagers access to guns post-Dunblane.

Moreover, there is the all-important question: will it attract the punters? While abseiling and other adventure activities look glamorous, the question is whether the cons will outweigh the pros.

Will the carrot of exciting activities prove more glamorous than having to wear a uniform, polish boots and learn to march? The current enthusiasm for the cadets comes from Defence Secretary Michael Portillo, who has recently decided to investigate the outlying posts of his empire.

What he saw convinced him - and also Prime Minister John Major - that this was what the nation needed. As the briefing from the Ministry of Defence explains: “The broad function of the Combined Cadet Force is to provide a disciplined organisation in a school so that boys and girls may develop powers of leadership by means of training to promote the qualities of responsibility, self-reliance, resourcefulness, endurance and perseverance and a sense of service to the community.”

However, the young Portillo was apparently not so convinced, and chose not to join his school’s own force. Another refusenik was John Major, who says he was too busy playing cricket in his school days.

As interesting are those parliamentarians who did join. Gillian Shephard apparently enjoyed her days as a Sea Ranger and is “interested” in the current idea. Tony Blair appears not to have been so keen on the whole thing. According to The Guardian, a good place to find him at cadet night at Fettes school was behind the cadet hut smoking a fag.

That is the point made by the scheme’s critics. Currently 241 schools have combined cadet forces - that is, covering Army, Navy and Air Force with individuals choosing which uniform they wish to wear. Just 43 of those are state schools, and there is currently nothing preventing others from joining. But they don’t, either because they are unaware of the possibilities, pupils are not interested or teachers do not want to volunteer to become a part-time Lieutenant, spending an initial weekend’s training at Frimley Green in Surrey before spending an evening a week training teenagers.

The CCF is currently by far the cheapest of the four Cadet options, costing Pounds 7.8m a year, and the MoD agrees that although there is no budget for expansion in practice there would be little problem if schools wanted to join up, since the necessary premises and volunteers would not be expensive.

Just what is being envisaged is somewhat sketchy. Newspaper stories have spoken of a cadet group in most schools staffed by ex-army personnel, insiders are suggesting a far more limited expansion with schools merely encouraged to join up.

John Sutton, general secretary of the Secondary Heads Association, said: “Precious few schools would be gone on this idea. Very few run them and I think that is a reflection on their capacity to deliver.”

The final argument is whether the cash could be spent more constructively. Tom Wylie, director of the National Youth Agency, says 20 times more is spent on the combined cadet force than the voluntary youth service.

Mr Wylie said: “What about some more support to the Scouts, Guides and Woodcraft Folk? What about a boost to the thousands of voluntary youth clubs building self-esteem and providing new experiences for young people, who like the young Major and Portillo, are not attracted to the military?”

What’s covered in the Cadets:

* self-discipline and personal appearance; * map reading, use of compass; * physical fitness; * adventure training; * expedition training; * first aid; * fieldcraft and minor tactics; * music.