MP or Time Lord – the key criterion should be talent

Age matters acutely for politicians as they struggle to appeal to the entire population

Margaret Thatcher with 16-year-old Rother Valley schoolboy, William Hague, after he received a standing ovation from delegates at the Conservative Party conference in Blackpool. Hague's first attempt to enter the world of Whitehall politics was blackballed by Thatcher, newly released government papers reveal (PA)

At what age does one go from gimmick to promising newcomer? And from newcomer to old hand? And from old hand to past it? It’s a perennial puzzle, especially for politicians, who, once elected by some of the people, must endeavour to appeal to or at least understand the ideals and interests of all of the people, whether 18 or 80 years old.

You would think that if any politician could navigate these tricky straits, it would be William Hague, a man blessed with both the face of a Dutch Renaissance baby and the voice of an octogenarian extra on Emmerdale. But even he has fallen foul of the age trap. It emerges in newly released Downing Street files that Margaret Thatcher vetoed Hague’s appointment as special adviser to the Treasury when he was 21, because he was too young. “NO!!!” she scrawled. “This is a gimmick and would be deeply resented by many who have financial and economic experience.”

How times have changed. In a world run by tech billionaires still in college hoodies, youth is no longer a gimmick. In David Cameron, the country has its youngest PM in almost 200 years – and yet his years, or lack of, rarely come up.

Did Thatcher have an optimal age in mind when she vetoed Hague’s move into politics? It’s hard to work out what that might be. Too young, and they may never win the confidence of older voters. Too old, and they risk alienating the next generation. Perhaps it’s 49 – bang in the middle of 18 and 80, the moment at which unsullied passion and jaded experience are held in perfect counterbalance. Or perhaps there is no magic number and politicians should realise that, like parents at a child’s party, they can’t win, and trying too hard only makes it worse.

The same No 10 files reveal Thatcher took a softer line on one Oliver Letwin, put forward for a Department of Education post, aged 26. “Oliver, after a brilliant career at Cambridge has just come back from Princeton,” ran the memo. “You know his parents Shirley and Bill...” It’s not politicians’ youth that’s the worry. It’s their old-school connections.

Peter Capaldi, best known to television viewers as The Thick of It's swivel-eyed, sweary Malcolm Tucker, is the new favourite to play Doctor Who. This week bookmakers slashed the odds on the Scottish actor succeeding Matt Smith in the role to 2-1.

Capaldi's rumoured move from spin doctor to Doctor conjures delicious visions of the Time Lord effing and blinding his way through Saturday teatime, withering Daleks with a single bulge of his eyeballs and a spittly bon mot. But that's the not the main reason to get excited about Capaldi clambering inside the Tardis. The main reason is that he is one of the UK's finest actors. Moreover, he is 55 years old, the same age that William Hartnell was when he became the first Doctor in 1963. Since then the character has grown more babyfaced with each regeneration – Christopher Eccleston was 41 when he took on the role, David Tennant, 34, Matt Smith, 27. A more mature, grizzled Doctor would be a welcome sea change, a fitting nod to the programme's past and, while we're at it, an opportunity for the BBC to demonstrate its new stance against ageism.

On top of all of that, having seen Capaldi's gloriously eccentric turn as Professor Marcus in The Ladykillers in the West End last year, I recall that he also carries off a long, woolly scarf with style. So, yes, Tucker for Time Lord – I'd watch that.

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