Withdrawals from Afghanistan should not take place in line with election timetables, former defence secretary George Robertson has said.
Speaking at the foreign affairs thinktank Chatham House, of which he is now president, the former Nato secretary-general warned that the war on terror would "once again engulf the world".
Lord Robertson is concerned by Britain's plans to end British troops' combat role in Afghanistan by the end of 2014. He told the Commons yesterday that next year will see nearly 1,000 of Britain's 10,000 soldiers withdrawn from the country.
"If the Taliban managed to win against NATO, and that's precisely what a premature election timetable-driven withdrawal would mean, then the shock waves will certainly not stop in Afghanistan," he said. "The parasite Bin Ladenites will return to their favoured terrain."
Lord Robertson said the debate in the United States was taking place in the context of the US primary and presidential election framework - while in Britain the next general election date appeared to be the key factor.
"In neither case are we transmitting the idea that withdrawal should be based on success on the ground and on the defeat of the enemy," he added.
"We parade our weaknesses and we undersell our manifest successes. We debate withdrawal, its pace and size, without reference to what we leave behind and we do so as if the antennae in the Afghanistan/Pakistan border regions and in the Tripoli basements don't pick it up. Be aware they watch every move we make."
Both the US and the UK have made clear they do not see a future for Libya with Muammar Gaddafi in charge.
But military support for Libyan rebels has not resulted in the collapse of the renegade colonel's regime, leaving Lord Robertson concerned at the qualified nature of Britain's commitment.
He emphasised the important of psychology in demoralising the enemy, as well as the important of preparing for victory.
"The enemy whether in Tripoli or in the Tora Bora caves needs to know precisely why we are there and why they have to be defeated," he explained.
"Constant repetition and reinforcement of the mission and the message 'Nato does not
do losing' is an absolute requirement."
In the latter stages of the Kosovo conflict, he said, reinforcement of peacekeepers in Macedonia proved crucial in convincing Serb commanders that the conflict was coming to an end.
He asked: "In the case of Libya, why are we not already planning for the stabilisation force which will be required if Col Gaddafi's mercenary force capitulates?"