The army officer whose speech to his troops in Iraq brought him global fame has called on the government to reverse planned defence cuts.
Lt Col Tim Collins in Iraq
Colonel Tim Collins - a guest speaker at the Conservative conference in Bournemouth - said it was no time to reduce Britain's defences.
And he warned cuts would affect the standard of training - potentially putting battlefield troops at risk.
He said cuts would relegate the British army to the "also-rans of Europe".
Paraphrasing Einstein, Col Collins, the former leader of Royal Irish brigades in Southern Iraq, spoke of the struggle between a "growing circle of light" and a circle of darkness enveloping the world.
He said the UK army's strength lay in its training regime and planned cuts threatened to undermine that.
"If training is reduced, then we will be incapable of producing a high standard, unless it's by accident.
"And then we leave our young men and women, open and liable to death and destruction on the battlefield and we can't afford that."
Colonel Collins said his brigade had seen action every year since 1994.
"If you have ambitions as a nation to get involved in operations on that scale then you must support your armed forces as they take part in those operations".
"The United Kingdom is a global trading nation, with a global outlook. It needs armed forces that are able to respond to back up its trading capacity."
He said the armed forces needed to be "agile, credible and effective" in "the eyes of its enemies," adding that the regimental system was the "backbone" of that capability.
He said there was no doubt the UK was engaged in a war and it could not choose to walk away from it.
'Light of liberty'
"Einstein said, in the context of knowledge, as the circle of light grows larger so the circumference of darkness around it increases. That holds true of liberty.
"The British forces, alongside our American allies, are bringing the light of liberty to nations that have suffered under despotism up until now.
"As they do so, the circumference of darkness and enemies and their insidious ability to attack us even here in the United Kingdom increase.
"It is no time to be reducing our armed forces. It is no time to be reducing our defences," he told Tory representatives, who gave him a three minute standing ovation.
'Boots on ground'
The Tories say they would end Labour plans to axe historic army regiments and warships if they win the next election.
In his conference speech, the party's defence spokesman Nicholas Soames also hit back at Labour claims he would cut defence budgets.
He set out plans to spend £2.7bn more on frontline defence than Labour over the next three years.
"For months it has been Labour's big lie that we will cut defence. After this announcement that lie can never be peddled again."
Mr Soames said the Tories would ensure "enough boots on the ground" to meet the army's commitments.
He attacked what he said was Labour's "ignorance" of the armed forces, and said the government was guilty of failing to provide British troops with the equipment they needed.
And he said cuts to the Royal Navy's fighting strength meant it would fall below that of the French for the first time since the 17th century.
Plans to scrap three frigates and to axe historic army regiments would be dropped under the Tories, he said.
He said his spending plans would be made possible by efficiency savings identified by the James Review and cash savings in other departments.