A Smashing First Act; Gordon Brown makes a stunningly successful debut as leader.(British Prime Minister Gordon Brown)

Byline: D'Ancona is editor of The Spectator.

It is ironic that, in his first week as prime minister, the most embarrassing mistake made by the famously numerate Gordon Brown was to miscalculate the number of days he had been in charge. Asked by David Cameron at his first Prime Minister's Questions why he had not banned a particular Islamist group, Brown said: "I think the leader of the opposition forgets I've been in this job for five days."

Actually, by then he had been in No. 10 for seven days. But we always knew that the weekly ritual of Prime Minister's Questions would be a nervous chore for Brown, never a political actor or orator of Tony Blair's caliber. Much more striking was the overall success of the new P.M.'s first week. The man who was expected to be ponderous and dispiriting has been fleet of foot and sometimes dazzling.

Many predicted that Brown would have a detailed plan for his first 100 days. What he grasped was that it is the first 100 hours that really count. In his 10 years as chancellor of the Exchequer, Brown was often derided as conspiratorial, dour and unpleasant. So his first task was to shed this image. Every incoming prime minister reshuffles his cabinet, but Brown declared that his would be a "government of all the talents."

This meant promoting the Labour Party's young stars, such as David Miliband (who takes over as the youngest foreign secretary in 30 years); James Purnell, the Culture secretary, and Ed Balls, the Schools minister. It meant showing clemency to close allies of Tony Blair who had been sharply critical of Brown as chancellor, such as John Hutton. Most controversially, it meant bringing those from outside the Labor Party into government: a former Tory, Shaun Woodward, is now Northern Ireland secretary. As chancellor, Brown loved cliques and factions, not least because he was often plotting against Blair. Now he proposes to govern "inclusively," saying he has "listened and learned."

The hard part will be to translate his bounce in the polls into resilient public confidence, and to restore trust in a government tarnished by spin and the turmoil in Iraq. There was deep symbolism, therefore, in Brown's decision to make constitutional reforms his first major policy announcement, designed to bolster the accountability of the executive, strengthen Parliament and end what became known under Blair as "sofa government"--government by a gang sitting in the prime ...