The precedents are good: New York, Paris, Barcelona, Berlin and Moscow all have elected mayors identifiable with the city's joys and woes. I once saw an irate grandmother brandish her umbrella at Yuri Luzhkov in protest at the state of the drains in the Russian capital. A mayor is the person we can trounce with our umbrellas when all the intermediate institutions have passed the buck. Because they need our votes next time, they are obliged to take notice.
In three weeks time, Londoners will vote in a referendum on whether they want a mayoral system and it would be extraordinary if they did not approve it. At this point, the familiar, metallic voice of Ken Livingstone will announce, repeatedly and loudly, that he covets a place in the approved list of Labour candidates.
Mr Blair very much does not want his first mayor to be Ken Livingstone. Been there: done that. Ken is about as Eighties as the Human League and Loadsamoney; and New Labour is in denial about the Eighties. It prefers not to associate its present comely form with the days when, as head of the Greater London Council, Ken could ban a champagne bar in County Hall as elitist and run minorities policies that kept the Tory tabloids in jokes about Irish, black, one-legged lesbians running self-defence classes for toddlers.
Ken is a living reminder of all that. Worse still, he is a reminder that a lot of Labour activists thoroughly enjoyed it - especially the feel- good gesture politics - the rocking against this, marching for that and rallies supporting the other, which Mr Blair finds silly and which alienate more prosaic souls.
The GLC was not the unquestioned success that Ken would have us believe. Both bureaucratic and wasteful, it pandered to the tastes and prejudices of middle-class activists. The flagship "fares fair" policy of cheap public transport caused havoc by encouraging too many people to use a system that was - and still is, heaven help us - in need of a structural overhaul. But in the end, as a victim of la belle dame sans merci at her most imperious, Ken won lasting sympathy. Lady Thatcher's decision to abolish the GLC made him a martyr to the cause of London.
The Millbank Tendency's response to this is straightforward: Ken must be stopped. The party's commissars are chewing their ballpoints right now, hatching plots to stop him appearing on the approved short-list. They will argue that his criticisms of New Labour policies have been so grave as to constitute outright disloyalty. Truly, Livingstone is not a natural-born Blairite. The last time I debated with him, he predicted an economic crisis that would deny Mr Blair a second term. He did not appear regretful at the prospect. Ken is at home in a recession.
But he is a member of the party's National Executive Committee, an honour to which he beat Peter Mandelson in a party-wide vote last year. It is in the name of the NEC that the vetters will decide the short-list for the mayor's job. So, it would be churlish and undemocratic to deny 50,000 London-area members a chance to vote for him.
The tactical alternative is, apparently, to put up Tony Banks, the last leader of the GLC, now a neutered enough Leftie to be Minister for Sport. To which I say: accept no substitutes. There is something about New Labour's make-over of Mr Banks that is deeply fake. He has become a house-trained pole-cat, both ineffectual and gaffe-prone. Frank Dobson, a good Old Labour vintage, doesn't want the job.
Surely, they're not serious about Glenda Jackson. Ms Jackson is oddly lacking in the very quality of showbiz appeal the job requires. She has buried her actress personality in an attempt to be taken seriously. But a London mayor should be like the city - stylish without being glamorous, a touch vulgar without being brash. Clare Short would be perfect - but her loyalties will remain with Birmingham. You can see the problem. New Labour has promoted a cast of frightfully polite people, unthreatening but bloodless. Right now, they are combing the ranks for anyone vulgar enough to take on Lord Archer but not wayward enough to embarrass Mr Blair.
Why do I care so much about Mr Livingstone's fate? Come the mayoral race, my vote would probably go to someone safe, like Chris Smith or Trevor Phillips. But banning Ken from the contest would be a mistake, both because of what it says about New Labour and what it says about Mr Blair's approach to local democracy. It would reveal that, after a landslide election- win and a blinding first year in power, he still does not trust his party to choose a modernising candidate over a socialist one. New Labour will never know its true strength until it allows real contests between right and left.
Mayors are there to do battle for their city. That means fighting central government for power and money. Devolution and the revival of local democracy are not processes that can be controlled centrally, although Mr Blair sometimes gives the impression that they can. The Scottish parliament will demand tax-raising powers. Rightly so - they are what differentiates a real parliament from a placebo one.
Elected mayors, in London and then elsewhere, will strain at the fiscal leash the Treasury has fastened to them. Responsibility for transport, police and the emergency services are just the start. Any mayors worth their salt will want to put their own projects to the voters, and seek their own solutions to infrastructural problems. In so doing, they should be answerable to the people who elect them, not enslaved to Whitehall.
The campaign to stop Ken is an example in miniature of New Labour's tendency to promise decentralisation and then inhibit choice from the centre. But local democracy means allowing people to make their own decisions and their own mistakes. As mayor for London, I would view Ken as a mistake. That doesn't mean that the Labour Party should deny voters the right to make it.