You could refuse to sell arms to nasty regimes abroad, then, and still avoid throwing people out of work at home. But he also knew that the dilemma at the heart of an ethical foreign policy is not so easily swept aside. "It's a matter of political life that you're not loved by all the people all the time." But Britain is ready to take the flak, even if business leaders complain about potential loss of contracts.
In an interview with the Independent Mr Cook acknowledged difficulties ahead. "Any government that pretends it is able to manage a consistent policy to 190 countries simultaneously is living in the mindset of a computer rather than the real world." But there would be no double standards: "There is no question of shrinking from difficult questions raised by large countries ... no question of us picking on the little guys and letting the big guys go."
Earlier he presented what was officially described as "his vision for putting human rights at the centre of British foreign policy". The setting was the Foreign Office's Locarno Room, the immediate backdrop a dais in a New Labour designer shade of grey, bizarrely enlivened by the jarring yellow and orange of Edvard Munch's Scream.
In a signal of the Foreign Office's declared openness to different viewpoints, his invited audience included representatives of Amnesty and 100 other non-governmental organisations. No less symbolic was the presence on the rostrum of the independent Tatton MP and former war correspondent Martin Bell, who championed the need for a morally based response to the war in Bosnia.
Until now, Mr Cook's policy has been largely confined to verbal gestures. None the less, if his words are only half matched by deeds, it will represent a radical departure. Not since Jimmy Carter occupied the White House has any Western government so publicly nailed its foreign policy to the mast of morality - and certainly not the government of a country so traditionally identified with hard-nosed realpolitik as Britain. But Mr Carter's pursuit of human rights helped undermine Soviet totalitarianism, and the New Labour Foreign Secretary sees no reason why, in this post-Cold War world, the formula should not yield new successes.
Mr Cook is unwilling to be drawn on how great a shift this represents from the last government's pragmatic priorities. "I don't want to get into the business of playing the superior political party on this issue. I would like to create a national consensus."
In one respect at least, Mr Cook is prepared to break new ground. He seems ready to extend an olive branch to those with politics diametrically opposed to his own. "In the US the Republican right feels as strongly on [human rights] as any member of the Clinton administration. You can detect that in the younger generation of new right-wing writers in Britain; some of that influence is coming through. If the right in Britain was to adopt some of the attitude of the right in America, I would welcome that."
He made it clear that the days when it could be said that "We have no friends and enemies, only interests," are over. "The commitments I made today are pragmatic, down to earth and serious. I get a bit fed up with the world-weary cynicism of some who feel they've seen the whole world go by. That seems to me to fit the mindset of a declining nation ... Robust confidence in our values is part of our national interest."
Mr Cook has been criticised for the apparent contradiction in policy of selling military equipment to Indonesia when Jakarta is under fire for its human-rights breaches. Yesterday he said the results of a review on the criteria for licensing weapons for export would be published "shortly". The review would result in "changes to the present policy" of sale of small-arms and other military equipment for sale to the security forces of "certain regimes."
On China, he told critics of its rights record not to hold a gun to Britain's head over its diplomatic and trade relations with Peking.
Mr Cook insisted there could be no question of Hong Kong's interests being sacrificed at the expense of good commercial relations with China. But he warned the democrats against too much doomsaying.
Last week's swoop by British forces against two alleged war criminals in Bosnia "represented a new resolve" by the world community to take tougher action there.
Next week Mr Cook goes to former Yugoslavia. A trip to Belgrade has been cancelled because President Slobodan Milosevic is "too busy" to receive him, which may be perceived as a backhanded compliment to the Foreign Secretary's tough stance on rights.
It is unclear how productive the "Cook doctrine" will be. As he acknowledges, in any rights case bilateral pressure can achieve only so much and multilateral pressure will be far more effective. But here too Britain has cards to play - the permanent UN Security Council seat, its Commonwealth role, and coming presidency of the EU. "We won't always succeed ... But we can use our influence to shift that common position a little further forward."