DAVID CAMERON found himself at odds with Baroness Thatcher last night after the Conservative Party leader made a speech criticising Britain’s “slavish” relationship with the United States.

While Mr Cameron attacked Tony Blair for his “uncritical” dealings with President Bush, his predecessor used a rare visit to Washington to insist that Britain and America must not be divided over the War of Terror.

In a statement released through the White House, Lady Thatcher said: “This heinous attack upon America was an attack upon us all. With America, Britain stands in the front line against Islamist fanatics who hate our beliefs, our liberties and our citizens. We must not falter. We must not fail.”

The former Prime Minister was in Washington, at the invitation of Dick Cheney, the Vice-President, for the commemoration of the 9/11 attacks. She struck a different tone from Mr Cameron, who sought in his first big foreign policy speech as leader to distance himself from Mr Bush.

Mr Cameron told an audience at the British-American Project: “We have never, until recently, been uncritical allies of America . . . I worry that we have recently lost the art. I fear that if we continue as at present we may combine the maximum of exposure with the minimum of real influence over decisions. The sooner we rediscover the right balance the better for Britain and our alliance.”

Mr Cameron’s aides sought to play down differences between him and Lady Thatcher, saying that his speech emphasised the dangers of anti-Americanism and the importance of the special relationship.

Mr Cameron used the speech to outline how his foreign-policy principles differed from Mr Blair’s, implicitly criticising the decision to invade Iraq. He stopped short, however, of suggesting alternative solutions or that the Conservatives would have done things differently.

Despite having voted in favour of the war in Iraq, Mr Cameron made clear his opposition to the idea that democracy can be easily introduced by military force. “Liberty grows from the ground. It cannot be dropped from the air by an unmanned drone,” he said, citing South Africa and India as cases of change being brought about peacefully. “Bombs and missiles are bad ambassadors. They win no hearts and minds; they can build no democracies. There are more tools of statecraft than military power.”

Tim Montgomerie, who runs the website ConservativeHome, said that the speech was balanced but lacked detailed policies. “I think the situation around the world is deteriorating extremely fast,” he said. “What we don’t have is the sense of immediate action on Iran going nuclear and we don’t have any strong sense of a plan to address missile defence.”

Mr Cameron’s spokesman said that the speech had been deliberately broad-brush. “He did not give a tick box of all the world’s problems. Foreign affairs is fast-moving and he has to act responsibly.”

In his speech the Tory leader also called for a more multilateral approach to solving global conflict, but said that international institutions, including Nato, the UN, and the European Union, often found themselves unable to act, such as over the crisis in Sudan.

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