Twenty years ago today, within the ornate golden walls of the foreign office’s Locarno room, Robin Cook set out the incoming Labour government’s mission statement on foreign policy. He committed Labour to protect national security through Nato, to promote exports, and to prioritise the environment. Then, introducing his fourth objective, Cook said: “Labour does not accept that political values can be left behind when we check in our passports.” He added: “Our foreign policy must have an ethical dimension, and must support the demands of other peoples for the democratic rights on which we insist for ourselves.”

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Last week, in a similar setting at the state department, Rex Tillerson – Cook’s modern-day American counterpart – defined his own mission. “It is really important,” he said, “that all of us understand the difference between policy and values. Freedom, human dignity, the way people are treated – those are our values, not our policies.” An over-emphasis on values, he explained, “creates obstacles to our ability to advance on our national security [and] economic interests.”

Where Cook saw promoting human rights as indivisible from protecting national security and prosperity, Tillerson sees them as irreconcilable.

If Donald Trump [ignored and abused our] values, we would criticise him openly, as we would do any other leader

So where does the Conservative government stand? Just look at its record. Training Bahrain’s security forces to use sniper rifles and water cannon. Arming the Saudi planes that have killed thousands of innocent civilians in Yemen. Proclaiming their “shared values” with Rodrigo Duterte, the murderous president of the Philippines. Turning a blind eye to human rights abuses in China. Courting trade with Sudan’s deadly leaders. Promising to “champion” Egypt’s brutal regime. Chastising European leaders for objecting to the threatened hanging of political prisoners in Turkey. And of course, Theresa May holding hands with Donald Trump, just moments before he signed the grotesque Muslim travel ban, epitomising her fawning obeisance to Tillerson’s boss.

What would Labour do differently? As our manifesto will make clear, we will not just return to the Cook doctrine, but take immediate steps in government to enact it. Like Cook, we will root our national security in the Nato alliance and defend British interests at home and abroad, and as he promised in the Locarno room, we will strive to reduce not increase global tensions, and give new momentum to talks on non-proliferation and disarmament.

Like Cook, we will work to increase British exports and build the global prosperity from which all trading countries benefit, while ensuring that climate change remains at the top of the international agenda, and that all countries stick to their Paris treaty commitments. And, like Cook, we will put human rights back at the heart of foreign policy.

Facebook Twitter Pinterest Trade secretary Liam Fox, who said he ‘shared values’ with Rodrigo Duterte, the murderous president of the Philippines. Photograph: Daniel Leal-Olivas/AFP/Getty Images

We will demand an independent UN investigation into alleged war crimes in Yemen, and suspend arms sales to the Saudi-led coalition until it is concluded. We will review all training and equipment contracts with Bahrain and other repressive regimes, to ensure that Britain is not colluding – however inadvertently – in the mistreatment of civilians. From China and the Philippines to Turkey and Egypt, we will tell every international partner that offering an open hand on trade and security does not mean turning a blind eye on human rights.

Labour will work with other progressive governments to help fill the gaps left by Trump’s cuts in funding for women’s empowerment and the promotion of democracy in the developing world. And from day one we will stand up to his administration, making clear that the special relationship is based above all on shared values, and that if Trump continues to ignore and abuse those values, we will criticise him openly, as we would do any other leader. None of this will happen under the Tories.

Indeed, if they are returned to power next month, let alone with a bigger majority, things will deteriorate further on human rights.

Sliding recklessly out of Europe without a deal to protect British business and jobs, the Tories will be so desperate for trade deals with the rest of the world, no partner will be beyond the pale.

Worse still, a disregard for human rights leads to disdain for the human consequences of war.

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If she wins on 8 June, as a fresh act of devotion to Trump, she will call an immediate vote on military action against the Syrian government. Not only would that escalate and prolong the war in Syria, it would risk bringing us into conflict with Russia and Iran – and all without any UN agreement or authorisation.

Whereas Cook came out of the 1997 election wanting “to secure the respect of other nations for Britain’s contribution to keeping the peace of the world”, May goes into this election already planning a unilateral act of war. No surprise from a prime minister who was recently asked four times to accept that Iraq was a mistake, and four times refused to do so.

Twenty years ago, Cook saw Britain choosing between becoming “a leading partner in a world community of nations” or continuing “the Tory trend towards not so splendid isolation”. How appalled he would have been now to see the Tories not just trending but hurtling towards isolation: destroying our relationships with Europe; planning unilateral military actions; and treating British values not as something to be promoted overseas, but to go tactfully unmentioned for fear of upsetting the Chinese or the Saudis.

We have the chance to restore our role as a world leader, to defuse global tensions rather than escalate them, and to put human rights and the environment back at the heart of our foreign policy. In short, as Cook put it, the chance “to make Britain once again a force for good in the world”. That was his mission 20 years ago for Labour and for Britain. It is not too late to do his legacy proud.