Now only Clare Short stands out from a grey Cabinet

And then there was one. With Mo Mowlam announcing that she will step down as an MP at the next election, only Clare Short is left to stand out from the greyness that is the new Labour Cabinet. Expansive, spontaneous and unbiddable, the two women have taken it in turns to be the thorn in the government's side. Ali can't get them to mind their ps and qs, and Tony can't quite bring himself to trust them. Yet these brassy gals are undeniably popular with the people, and so the uptight new Labour lot had to put up with the four-letter words, the gaffes, the tampon shopping expedition. But look at any photo that captures the PM next to his Secretary of State for International Development or beside his Cabinet Office Minister: he's cringing, almost visibly gritting his teeth, and completely dwarfed by the Big Woman. Look at the Blair expression and you can make out his unspoken wish: that maybe, just maybe, these Big Women will go away. Well, one has.

A shame. Mo and Clare belong to that increasingly rare breed - the larger-than-life politician. The Tories can boast Ann Widdecombe and London has Ken Livingstone; but otherwise, we're stuck with the politics of the little people - smaller-than-life creatures who shrink parliamentary democracy into a drab non-event. Buttoned-up and tight-lipped, these colourless gnomes seem capable of producing only neat little soundbites and manageable policy packages. They feel comfortable only in circumscribed spaces, with narrow vistas: anything that smacks of great ideals or big ideas - whether it's overhauling the NHS or subscribing to the European project - has them running for cover.

Politicians used to come in bigger sizes. Churchill, Thatcher, Benn, Tebbit, Barbara Castle: always colourful, often OTT, they gesticulated madly and railed furiously and made a spectacle of themselves. Michael Heseltine and Paddy Ashdown were in the same mould, although more swashbuckling and almost romantic. They all stuck their heads above the parapet and took everyone and everything full on. A Heseltine lambasting or a Benn jeremiad was a spectacle that showed the Commons was more than a stop on the London sightseeing bus. The media loved the show, the overblown oratory and (yes, let's be honest) the unrepentant egos that turned dreary Westminster business into a highwire act. And between press and politicos, an easy complicity was forged that bears no resemblance to the cloak-and-dagger game that both Blair and Hague play with the press today.

The oversized politicians fired our imaginations with visions of a shining future in which we would all have to play a heroic part. This is one of the consequences of being larger than life: you think others are built along the same lines, as capable of shouldering burdens as you are, as strong in their beliefs. You are incapable of the condescension that is the little politician's defence. As a result, you create a people in your own image - as Churchill did during the war, as Thatcher tried to do in the 1980s. Politicians such as these add up to more than the sum of their parts. They don't just govern, they inspire; they don't just inherit a set of goals, they refashion society.

Today, party politics wants to cut them down to size. They are seen as troublesome, "off message". They are assigned minders and given briefings. Eventually, they break away from the grey control tower. Thus, Ken went it alone in his campaign for Mayor of London; Benn decided to retire from Westminster and won't hear of running for Speaker of the House; Heseltine is publishing his memoirs. Mo is an even greater loss. She is Britain's most popular politician, one of the few who lent new Labour some colour and hinted that there were hearts beating within the automatons.

It's now down to Clare Short. She must step into the big shoes of the larger-than-life politician. And if they know what's good for them, her bosses will let her.