Andrew McKie: A very radical budget that, politically, looks extremely astute

But yesterday's Budget was less about urgency than emergence. The first wholly Conservative budget for 19 years let the Chancellor get out of the restraints placed on him by the Liberal Democrats.

Questions about the sums, particularly the mooted £12 billion welfare cut, loomed over the Tories because, like most looming things, they were both huge and vague. The general assumption - probably Mr Osborne's assumption - was that this didn't matter because they were a starting point for horse-trading with Coalition partners rather than promises carved on a huge stone tablet, if you can imagine any politician capable of doing something so self-evidently idiotic.

So, once free and given a mandate to do what he wanted, the first thing Mr Osborne did was to cut himself a little slack, £83bn worth. The second was that, given the chance to introduce a wholly Conservative budget, he stole its most startling policies from the Labour Party's manifesto.

Thus we had the bizarre spectacle of Iain Duncan Smith pumping his fists like something out of Agadoo over the Government's plans to introduce a new national minimum wage of £9 an hour, as opposed to the £8 an hour pledged by Ed Miliband, which Tories claimed was ludicrous and unaffordable a few weeks ago. Calling it a "living wage" is a silly piece of political legerdemain, but it makes it pretty difficult for the Left to oppose, especially if it could - as is promised - create one million jobs while endangering just 60,000.

There were predictable Tory cheers for cuts in corporation tax to 19 and later 18 per cent but also for the scrapping of permanent non-dom status, something that, way back in April, they were sure would imperil the country immeasurably.

The restriction of interest rate tax relief on buy-to-let (BTL) properties to the basic rate is a huge alteration for landlords - since 15 per cent of new mortgages are BTL, that means a lot of small investors - and it's likely to have a significant effect on property prices.

That, as it happens, is a thoroughly sensible and long-overdue closure of a racket, as is making firms such as Tesco and Asda pay for their own employees, rather than letting the taxpayer subsidise them. But they may not be policies that please a lot of natural Tory supporters or corporations. Tough.

If, on welfare expenditure, the Chancellor intended to reverse Gordon Brown's ludicrous tax credits system, which drew as many people as possible into the maw of the welfare state and costs 30 times what it did when introduced, it was not only necessary but consistent to get rid of subsidies to the payrolls of big corporations. It is, after all, a distortion of the market which has benefited them, and to which they responded by paying not only the lowest wages, but the lowest taxes they could get away with.

Perhaps the central point about yesterday's announcements, however, is that in every way - as the Office for Budget Responsibility confirms - they were a loosening of the targets which the Chancellor had set himself and a slowdown in the plans for cuts and deficit reduction.

That's not to ignore the fact that the tax credit cuts to many household incomes will be significant and painful. Half a million people will lose tax credits, and 300,000 will drop out of the Universal Credit system. Despite the Chancellor's habitual rhetoric, it looks as though most of those will be "deserving, aspirational, hard-working people"; that is, low-to-middle income households rather than the very poorest.

Nor does it alter the fact that, if things go to plan, he will have reduced the welfare budget and the deficit by the headline figures he had set himself, though more slowly. Substantial though it is, the £19bn to be raised over the five-year period of this Parliament is less than half the sum found in Mr Osborne's first budget.

This breathing space is politically important, even if not economically sensible, because it builds in grandfather clauses for the most painful cuts for individuals. The sizeable reduction in support for families with more than two children, the substantial cuts to student finances (in England), the freeze on working tax credits (except statutory ones) and the reduction of the caps on both direct benefits and housing benefit will have a serious adverse effect on many people's finances.

But not yet; and not, to a large degree, for those who get them at the moment. There's a big difference between not having a future entitlement and having something you already have taken away. Mr Osborne is often attacked by his opponents as puritanically ideological and excessively strict economically. His instincts may be, but his budgets aren't.

They are thoroughly pragmatic and political, which is why some fiscal hawks are suspicious of him. There are a few puzzles, though. It's hard to see why he has reintroduced the Road Fund (as Vehicle Excise Duty has not been called since Churchill's day) but missed the opportunity, while prices are low and the economy is recovering, to reinstate the fuel duty escalator. It is true that efficient cars are cutting government income from this source, but it wouldn't even have been a tax rise, just a halt to the freeze he maintained for political benefit before the election. And ring-fencing benefits for rich pensioners is as idiotic as it has always been.

The difficulty for the Left is that, though welfare cuts will create real hardships for individuals, they enjoy popular support, while Mr Osborne's boosts to the lowest paid will be difficult to oppose coherently. The political advantage to the Tories is that, like the free TV licence for over-75s, the taxpayer won't pay for it.

Meanwhile, making corporations pay more tax and wages, the surcharge on banks, and the raid on property taxes will annoy business, but it is probably offset by the cut in corporation tax. This budget is so radical that a lot could go wrong. It may turn out to be an economic or social disaster. But from a political perspective, here and now, it looks very astute.