Gordon Brown has pressed the button

Gordon Brown has pressed the button and changed British electioneering forever. In a statement on the Labour website he’s given the go-ahead for head-to-head debates between the party leaders to start before the campaign proper, to be in a series – maybe three, maybe more and to take place round the country.

He also wants other senior cabinet members to debate with their counterparts – something he actually pioneered in 1997 as chancellor.

But he was generally not around that much in TV studios as chancellor … he behaved like a Trident submarine … long periods submerged (someone once calculated that he didn’t give a TV interview for 16 successive months) punctuated by brief bursts to the surface.

There was talk before he came to No.10 that he might do away with Tony Blair’s innovation of the monthly press conference. He stuck with it, now he is innovating more boldly.

Peter Mandelson was the first to say to the prime minister he thought he had to do it. Virtually all senior colleagues seem to agree. The prime minister, they hope, can deploy knowledge and experience to make the challenger, David Cameron, look callow and too much of a risk in dangerous times.

What all the prime minister’s team know too is that he has a temper, he doesn’t always come down from the intellectual Olympian heights to explain things for beginners (one cabinet minister lamented a couple of days ago how the PM never makes the mortgage/borrowing analogy that would help voters round the issue) and David Cameron has quite often (not always) been faster on his feet at prime minister’s question time.

I’m not sure our elections will now hinge on one bead of sweat or pause in a presidential-style debate. Our politicians are already usually more well-known to the voters than US presidential candidates who can come out of clear blue sky sometimes.

But there’s the worry that they might become the defining moment to the exclusion of everything that’s been said and done for months or years. The experiment is coming to a TV screen near you before too long.