Leading article: Time to stand in the path of the juggernaut

IT IS instructive to define a government by its enemies: Margaret Thatcher brought the ban-the-bombers and trade unionists on to the streets to protest, and stimulated the poor and disadvantaged to riot. So far the Labour Government has induced the Barbour-clad countryside to march on London, and the lorry-drivers to block Park Lane. Today, the lorries are coming again, aiming to jam the centres of six cities. In London, they are expected to be joined by taxi-drivers and pig-farmers. This unlikely coalition is no more likely than the miners and the disaffected youth of Brixton to bring the Government to its knees.

Some of the reversals of left and right since the Eighties are none the less piquant. To have The Daily Telegraph defend unlawful disruption by truckers brings back memories of left-wing commentators wringing their hands over picket-line violence. The Telegraph described the lorry-drivers' action as "desperate" but "understandable", and said expressions of "public tolerance, bordering on goodwill" should be a warning to the Government.

Any fair-minded observer should, however, condemn even-handedly any antisocial attempt by sectional interests to change Government policy in their favour. Especially in this case, when the broader public interest is clear. Gordon Brown was quite right in his Budget to continue the Conservative policy of annual real increases in petrol and diesel duty. (The notion that diesel was a "greener" fuel because it produces less greenhouse gas has been overthrown by the more direct threat to human health of particulates.) Congestion will do the job of limiting traffic growth - but it is more economically efficient to use prices to achieve the same end. While the sharp shift in road duty to discourage bridge-shaking, building-juddering, five-axle lorries in favour of smoother six-axle ones was overdue.

The truckers' main argument - apart from self-interest - is that the Budget tax increases are self-defeating, because haulage companies will run their juggernauts under "plates of convenience" from Luxemburg or Bulgaria. Norbert Dentressangle, the king of the big beasts of the road, has already announced 30 redundancies as he concentrates resources in the French part of his operation.

This is less of problem than the haulage industry pretends, though, because other corporate taxes are higher on the Continent. But the Government finds it difficult to counter this argument because the right response is to support some degree of tax harmonisation across Europe.

It should be said that the solution is not to get into a low-tax auction, with each country underbidding its neighbours. Britain should not lower its taxes on road transport, but seek to persuade its partners to raise theirs. It is the right way to preserve the environment and encourage rail freight. The Government must stand firm against the extra-parliamentary tactics of the New Scargillites.