When Robin Cook tried to tighten rules on British arms sales to dodgy regimes in 1997 he was told by Tony Blair's team to grow up. Planned changes to criteria for weapons exports were so watered down that they made no inroads into the trade. Cook's professed "ethical dimension" to foreign policy was stillborn.

Downing Street had been heavily lobbied, but it needed no convincing. This is one area where the boardroom and the unions are in harmony, and one that does not change whatever the government. Britain is a market leader in fighter jets, electric batons, sub-machine guns and teargas. Why add to the jobless total for the sake of morals? If we don't sell the kit someone else will.

The announcement, therefore, of a revoking of licences to Bahrain and Libya should be taken with a pinch of salt; I predict that British firms will be back at it as soon as the coast is clear.

The coalition government's commendable, but limited improvements in civil liberties at home have not been replicated in foreign policy, which is brazenly mercantilist. Go forth and flog Britain's wares is the message. The notorious Export Credits Guarantee Department, responsible for some of the most economically foolhardy and unethical business deals of the past 20 years, has been boosted. From arms sales to Saudi Arabia and Indonesia, to oil and gas pipelines in central Asia, to mega-dams in sub-Saharan Africa, the ECGD has backed projects that have been implicated in corruption, environmental destruction and human rights abuses.

At the weekend, the UK arms industry descended on Abu Dhabi for Idex, the region's most important weapons fair. A tenth of all the global exhibitors are from Britain. Gerald Howarth, the minister leading the delegation, declared that "we have ambitious plans".

The most unequivocal message since the election was made by Peter Luff, the defence equipment minister, who told a defence show in June: "There will be a very, very, very heavy ministerial commitment to arms sales. There is a sense that in the past we were rather embarrassed about exporting defence products. There is no such embarrassment in this government."

Indeed there is not. The regimes currently using brute force to put down pro-democracy protests are all longstanding partners of the UK. As the Campaign Against Arms Trade notes on Bahrain: in 2010, equipment approved for export included teargas and crowd control ammunition, equipment for the use of aircraft cannons, assault rifles, shotguns, sniper rifles and submachine guns. No requests for licences were refused.

Algeria, Egypt and Saudia Arabia have provided rich pickings for UK arms exporters. Of all the bilateral arrangements of recent years, perhaps the most despicable is the one with Libya. Colonel Gaddafi morphed from terrorist sympathiser to friend of the west, which then turned a blind eye to his internal repression. Libya is regarded as a priority partner, with the UK boasting the largest pavilion at the Libya's arms fair.

CAAT figures show that in the third quarter of 2010, equipment approved for export to Libya included wall-and-door breaching projectile launchers, crowd control ammunition, small arms ammunition and teargas/irritant ammunition. No requests for licences were refused.

Earlier this month, the trade minister, Lord Green, announced that ministers will be "held accountable" if companies fail to secure deals and foreign investors favour Britain's economic rivals. Beside him was business secretary, Vince Cable.

In opposition the Lib Dems were vocal about arms sales. In government they have grown silent. In January 2009, Nick Clegg wrote on these pages that Britain should stop supplying Israel following its bombardment of Gaza. He made a broader point: the UK should not supply weapons to countries involved in external aggression or internal repression. I have heard nothing significant from Clegg on the issue since he became deputy prime minister.

He may believe that if he spoke out, he might suffer a similar fate to Cook. There is too much riding on an industry that abets authoritarian regimes, while providing rich profits for UK firms and jobs. In the current economic climate, who would stand in their way?

• This article was amended on 21 February 2011. The original referred to a weapons fare and the Campaign Against the Arms Trade. These have both been corrected.