The new Conservative-Liberal coalition government in the United Kingdom marks its 100th day in office this week: How’s it doing?

It could be said that the Cameron-Clegg government is acting like a very traditional Tory government. In June, the government produced an austerity budget: spending cuts, public-sector pay freezes, a hike in Britain’s value-added tax.

Yet at the same time, the new austerity budget goes to great lengths to protect Britain’s poorest. The public-sector pay freeze exempts workers earning less than 21,000 pounds; those workers actually receive a pay increase. The poorest 10 percent of households will face an average of 400 pounds per year in reduced benefits and tax increases; the richest 10 percent will lose an average of 1,800 pounds. Capital gains taxes will be raised, and a special levy will be imposed on British banks.

Chancellor of the Exchequer George Osborne described the budget as “progressive.” That may seem a strange thing to say of an austerity budget. What Osborne means, however, is that his budget targets weak claims on the treasury rather than weak claimants (to borrow an old phrase of David Stockman’s).

When Cameron Conservatives describe their politics as “new,” Osborne’s equitable burden-sharing is part of what they have in mind. Part, but not the whole. What is also new in Cameron conservatism is the method and the tone -- as much or more than the content.

A generation ago, British and American conservatives came to power infused with a bold vision of a radical reduction of government. Much was achieved in those years, but conservatives also bumped into the limits of the conservative project. Those limits often proved surprisingly narrow: The momentum of the Thatcher government was wrecked over an issue that normally bores the British senseless, the financing of local government.

Why did conservatives fail to achieve more in their best days? Part of the answer was that they talked too big. Big talk frightened the public into assuming that conservatives accepted no limits, that they wanted to cut, cut, cut and would continue to cut, cut, cut until somebody stopped them.

Following Tony Blair's example, Cameron is careful not to frighten voters

Cameron conservatism seeks to correct that impression. It offers a self-limiting revolution: We go this far, but not farther. We have no secret agenda. Today’s budget cuts are not a first step on the slippery slope to the total abolition of social spending. Programs treasured by the public are accepted by us.

You might say that Cameron Conservatism is the bookend to Tony Blair’s Labor politics. When Tony Blair assumed the leadership of the Labor party, that party was still theoretically committed to socialist economics. The party constitution pledged outright nationalization of major industries:

“To secure for the workers by hand or by brain the full fruits of their industry and the most equitable distribution thereof that may be possible upon the basis of the common ownership of the means of production, distribution and exchange, and the best obtainable system of popular administration and control of each industry or service.”

Most Labor party members had lost faith in “the common ownership of the means of production” a generation before. Britain had last nationalized a company, British Leyland, back in 1976, and then only to avert bankruptcy and job losses. But the promise lingered on the books, nobody got around to abolishing it, and the question lingered in the mind of every British voter with something to lose: Will Labour deprive me of what I own?

In his first speech as party leader, back in 1994, Tony Blair answered those anxious voters: “Don’t worry.”

“It is time we had a clear, up-to-date statement of the objects and objectives of our party. … This is a modern party living in an age of change.”

Blair added for good measure that he would leave alone the Thatcher-era reforms in labor law.

“Even this week I have heard people saying a Labour government must repeal all the Tory trade union laws. Now there is not a single person in this country who believes that to be realistic, or that we will do it. No one believes strike ballots should be abandoned. So why do we say it? We shouldn’t, and I won’t.”

If you won’t do it, why say it? That could be the organizing principle for Cameron Conservatism as well.

There is a lesson here for American conservatives. Mesmerized by the Tea Party rallies, some Republicans have had an Ayn Rand conversion experience on the road to Wasilla. They have embraced a bold new rhetoric that denounces long-established government programs as “tyranny” and rejects concerns for the poor and unemployed as “socialism.” The rhetoric is no less dangerous for its emptiness. As British Labour discovered with its empty rhetoric in the 1990s, as Britain’s Conservatives discovered with their own in the 2000s, and as U.S. Republicans may yet painfully discover in the run-up to 2012.