Britain should give up trying to punch above its weight internationally and stop routinely deploying troops to world trouble spots, the chairman of the parliamentary committee that oversees the intelligence services said yesterday.
Kim Howells told The Independent that the succession of British deaths in Afghanistan proved the time had come to abandon the pretence that the UK could be at "the very, very sharp end" of United Nations military operations.
Mr Howells, a former Foreign Office minister, called for a fundamental rethink of the nation's place on the world stage.
He argued that the energy and resources used on fighting distant wars should be channelled instead into tackling security threats directly facing Britain.
Mr Howells, who is retiring as an MP at the election, said: "I think we believe we have a bigger punch than we have and a lot of that rests on the superb professionalism of the armed forces.
"When the UN needs a force that's actually going to do the business, they look to the Americans and the British. They don't look to other people."
He said: "We've always regarded ourselves, with justification, of being one of those nations riding on-point for the United Nations.
"So when there have been big problem – Sierra Leone, Bosnia – it's our troops who have been there at the very, very sharp end, in places of great danger. It can't continue."
He said the heavy price paid by UK forces was being reinforced weekly by the "extraordinary images" at Wootton Bassett whenever the bodies of soldiers killed in Afghanistan were flown home. "The public appreciate those ceremonies – they want the dead honoured, but they feel increasingly dubious about sending our troops on these missions.
"The more the reality of those casualties and the awful injuries is made available to the public, the more doubt there is about the wisdom of sending our troops to distant places with all of those risks."
Mr Howells, who has already called for Britain's withdrawal from Afghanistan, said: "I'm very worried we're concentrating on only one thing and that's defeating the Taliban in Helmand province, which is only one part of Afghanistan.
"We have to be realistic and take cognisance of the fact that terrorists won't limit themselves to particular areas – they will look for safe ground wherever it can be found."
He said he did not understand Barack Obama's tactics in dispatching 30,000 US troops as reinforcements to Afghanistan and feared the US President was simply "hoping for the best".
Mr Howells said: "It is said you have got to have a minimum of 500,000 combat troops if you are really going to police the country. A surge of 30,000 extra is going to be nothing like that."
The former minister said he stood by the decision to invade Iraq in 2003, but believed it should mark a turning-point in British military history.
He said the Iraq war demonstrated that most of Nato "were not prepared to put their troops in harm's way" and he saw no sign of that changing in future world crises.
He took a swipe at the Chilcot inquiry into the war as a "public spectacle" that served little practical purpose.
"We are obsessed in this country with inquiries. They cost an enormous amount – at the end, very few people believe the reports because people tend to continue clinging to whatever belief they had before the inquiry started."
Mr Howells, who has chaired the Intelligence and Security Committee since 2008, echoed the Prime Minister's warning that the terrorist threat is "constantly evolving". He added: "Their ability to radicalise and inspire highly educated people is extremely worrying."
He said he was not a "great enthusiast" for the controversial technique of "profiling" air travellers in efforts to thwart terrorists.
"As we look at terrorist incidents around the world, it's frequently those people who are not archetypal – they will use converts for example who look different. They do these things very cleverly."
He also called for sweeping reform of the United Nations which he said had a "pretty hopeless record" in peace-building, preventing war and tackling human rights abuses.