Leading Article: Look behind you, Mr Blair, your supporters are watching and wondering

This week, the Labour Government changed. The private grief, arguments and soul-searching among ministers and loyalist MPs were more important in that change than the resignations and public rebellion. They add up to a party in power that has hardened its face and lost its youthful, bouncy optimism.

The change, New Labour's unpleasant, painful rite of passage, was deliberately inflicted by the Prime Minister. There are a hundred ways in which Tony Blair, Gordon Brown and Harriet Harman could have avoided cutting the future income of some of the poorest families in the country. They know that politics, and not simply socialism, is the language of priorities. We now know that paying single mothers not to work, but to stay at home with their children, is not a New Labour priority.

Mr Blair argues that it is far, far better to push people into jobs. We agree. He points out that his party had been elected on the basis of sticking to Tory spending limits for a couple of years. Again, quite right: to breach those would have been to break faith with voters. This is particularly important at a time when many middle-class people who cautiously voted New Labour for the first time are totting up the various perk-removals and indirect new imposts agreed by Mr Blair, and asking themselves how they differ from old-fashioned tax increases.

But it does not then follow that these cuts at this time were the only option. Far from it; they were chosen. And if they hurt, they were meant to hurt, for two reasons. The first is ideology. Despite the refusal by ministers to respond directly to questions about whether they intend to drive people into work, the developing ideology of New Labour, like that of the New Democrats in the United States, is clear on the underlying issues. The party leadership believes that unchecked welfare and a dependency culture pose a moral threat to the nation. This is rarely stated openly - except by Frank Field. And it isn't the case that the Prime Minister is identical to any New Rightist on the matter: Mr Blair will do more to find jobs for people than his predecessors did. He is energetically convincing on the subject. But in his belief in the moral danger of dependency, he is a true heir of Margaret Thatcher. He wants people to work, above all. Work is the bedrock of New Labour thinking, even when it takes a few whips and scorpions to drive welfare-recipients towards it. Mr Blair is not a Tory. But he is not a liberal, either.

The second reason behind the cut is political strategy. The New Labour leadership sees no threat whatever from the left. Why? Because the kind of people who are conscience-stricken about last night's decision have nowhere else to go. A handful of individual MPs can resign, and rather more than a handful can rebel. But in the end, for them and their supporters in the country, there is no credible alternative force. The Liberal Democrats are the obvious challengers, but they are too geographically concentrated, and too close to Labour on other issues. The Conservatives are flopping about, dazed by Blairism, unsure which way to jump.

While all of that remains true, Blair's political priority is surely to dig ever deeper into traditional Tory territory, appropriating the rhetoric of pro-family, anti-welfare politics, reassuring the hard-workers at the expense of the shirkers. His base can be almost infinitely expanded - can't it?

We would say, watch it. The laws of political physics mean that, if the country was served a consistent diet of illiberal centrism, opposition would harden and grow. It would come not from some new force, but from the Liberal Democrats and from inside the Labour family itself. Look at what they feel already about cuts for the disabled. Labour is keen, loyal, and still power-hungry. But it is not infinitely flexible.

So look at the faces behind you, Mr Blair, and ponder their expressions: not this week's rebels, but the ones who didn't rebel, who are swallowing hard and are sick at heart. They are your people. They are not aliens or lunatics, but decent, mainstream politicians upon whose loyalty and good sense you will depend. This affair has touched their idea of themselves and their purpose in power. Much more of what happened last week will produce the conditions for a debilitating internal challenge. Imagine it: a cluster of politicians who pronounce themselves not New or Old Labour, but Free Labour, or some such tag.

Given our current electoral system, and the strong central discipline now exercised by Labour, we do not think ``Free Labour'' would thrive at the polls, or at party conference. Nor would the rebels pose the kind of day-to-day threat to the Government that John Major experienced from his Euro-rebels. But the emergence of a consistent and semi-organised opposition to Blair would be debilitating. It would wear down the party, produce a ready source of broadcast criticism, blur the Government's messages and erode its self-assurance. You don't need that, Mr Blair.