Boris Johnson: My priority from today is to stop these killings

In case there are some readers who may be tempted to think these numbers are not in themselves very large, let us remember that these teenage killings are not a series of freak events. Each fatal stabbing or shooting is at the apex of a pyramid of violence, thuggery and bullying that is making life less pleasant for everyone in the city.

No government, no mayor, no politician can claim to have a magic solution. We are dealing with huge social upheavals that have brought about a change in the power relationship between children and adults - a change as seismic and irreversible as the 20th century change in the relationship between men and women.

Some of the consequences of that change are good, in that children are generally less fearful of adults than they were when I was a child.

But in the sense that children are too often growing up without boundaries, and without respect, the consequences are disastrous - disastrous for the adults, too scared to assert their historic authority in public space; and when adults are reluctant to intervene, the results are disastrous for the teenagers themselves.

Since this crisis is at or near the top of the problems of modern urban life, it should be the number-one concern of a new Mayor.

I want to deal with the symptoms of the disorder - and I have already had talks with the Metropolitan Police and with Transport for London about getting more uniformed personnel on the buses. There will be more announcements on safer transport this week.

We are going to change the rules of carriage so that you no longer have the unsettling or frightening experience of sitting down late at night opposite someone who is not only drunk but still drinking - and who may be both sloshed and threatening. They don't tolerate it in America. I don't see why we should tolerate it here. We are going to get more police out there, where we want them.

As Mayor I will certainly be lobbying for much tougher sentencing. But we aren't going to crack our problem - and let me remind you, we are twice as likely to be mugged in London as in New York - unless we systematically attempt to deal with the causes.

That is why I am so proud that I yesterday appointed Ray Lewis as my Deputy Mayor for Youth and Opportunity. Ray is the founder of the East Side Young Leaders' Academy, and in a world where brains have been softened by political correctness, I sometimes think he is one of the few people who understands what needs to be done.

Ray's parents divorced when he was young, and at the age of about 12 or 13 he joined a boxing club in Waltham Forest. As he says, it was the making of him. He learned discipline, he learned respect, he learned how to control his temper. In other words, he learned the emotional maturity that is lacking in the perpetrators of knife crime today.

We are trying to cope with young people who take such swift offence at a slight - or imagined slight - that they will whip out a knife and wreck at least two lives with one blow.

Ray's approach has been to take young black males who have been excluded from school, and imbue them with magnificently untrendy bootcamp style discipline. He has been extraordinarily successful. He helps many of his students to perform a hand-brake turn in their lives. They win scholarships; they go on to university. Now he is going to join me in seeing if we can replicate his approach across London.

Of course it would be foolish to imagine that we can have a transforming effect overnight, but I am full of hope. Imagine what we could achieve with 100 Saturday schools like the East Side Young Leaders. Imagine if there were dozens of boxing clubs, rather than the handful that survive today.

This is about so much more than providing the distraction of a ping-pong table in a youth centre - though we could certainly do with more of those.

Go to the London Boxing Academy in Edmonton, and you will not only find kids exhausting themselves in the ring. They are also taking English and Maths GCSEs.

Bored, angry teenagers who have been shut out of school are not only enjoying the physical release of boxing, but finding a new path to educational qualifications.

My job as Mayor is not just to sort out our housing and transport problems, but also to champion and expand this kind of voluntary-sector activity. It means setting up the Mayor's Fund for London, and using the London Development Agency to match -fund donations.

The job also entails a willingness to say tricky things, and to propound such unfashionable concepts as competition, discipline and punishment. I was dismayed the other day to be warned that there were "issues" involved in taking away the right of free travel on the buses from kids who abuse it. Such action, I was told, might fall foul of the Government's "Every Child Matters" agenda.

I am afraid this kind of thing makes me impatient. Of course every child blooming well matters. But what about the kids who feel bullied and frightened by other kids on the buses? Don't they matter?

Someone needs to sound a word of caution about the expansion of children's rights, because there are now many London parents who worry that they are statutorily forbidden from offering any kind of discipline at all. That someone should be the Mayor.

I am convinced that we can make a real difference to so-called minor crime as a way of driving out more serious crime.

And even if it is a long, hard struggle to deal with the present culture of knives and gangs, that is all the more reason to make a start.