There is much evidence that the Taliban are less a fundamentalist religious group dedicated to sponsoring al-Qaida in international jihad and more an amalgam of groups seeking to fight foreign occupation and reassert the traditional dominance of the Pashtun group, which has largely been ceded to Tajiks and others, despite Karzai himself being a Pashtun (Brown will not walk away from fight but public support falters, November 6).

In this sense, Nato has helped to promote a civil war as well as resistance to what is seen by many Afghans as imperialist aggression, particularly by Britain, which has invaded Afghanistan three times.

Britain, the US and Nato should get out of Afghanistan and a negotiated settlement be sought involving regional powers and the Taliban, who may not prove dedicated to continuing to support al-Qaida's presence. This is the only way. Otherwise Nato will be forced to withdraw as Russia was only 20 years ago, after the death of 15,000 troops.

But terrorism cannot be properly fought by extra surveillance on the streets of Britain. The only way is to convince Muslims that the west is not against them. This must involve rapprochement with Iran and Syria, withdrawal from Iraq and above all a just settlement in Palestine. Then we might be getting somewhere.

Peter Rowlands

Swansea

• The wars in Afghanistan and Vietnam, though arising from different causes, have developed striking similarities in management. In both there was a decision to use a military invasion when other means were available. In both, a puppet leader was installed. In both the resistance to the military occupation was badly underestimated. In both the reason for the occupation was flawed (when Vietnam was finally lost to the communists, there was no domino effect on its neighbours, while the idea that our troops, by killing Afghans, are making the streets of Britain safer is unworthy of a reasoned rebuttal). In both there occurred growing public pressure for withdrawal of our troops, eventually successful as regards the Vietnam war.

Harry Davis

Thames Ditton, Surrey

• It is encouraging that Kim Howells (Comment, 4 November) has broken ranks and questions the wisdom of government continuing to deploy troops in Afghanistan. However, it does not follow that the money would be better spent on yet more intrusive surveillance of "certain communities". "Certain communities" in the UK are already the most intensively monitored in Europe, and there is no evidence that more of the same will make us safer. Indeed, excessive surveillance, if conducted poorly and without respect for rights, will reinforce the very alienation that leads some young people towards political violence. Rather than lobbying for more surveillance, the intelligence and security committee should oversee the spreading police and intelligence networks so they focus on those that intend harm while respecting rights of dissent.

Peter Gill

University of Liverpool

• Gordon Brown deserves our support over Afghanistan. It is true that in the past western armies have failed there, but that does not necessarily mean that they will fail again. The case for staying is complex, and it is easy to say that it would be cheaper simply to guard our own shores. However this would not prevent a 9/11 type attack, planned and provided for in Afghanistan. We must fight terrorism at its source, while defending at home.

Anthony Garrett

Falkland, Fife

• Josh Arnold-Foster (Response, 6 November) says people who "applaud our brave forces" also support the wars involved. Support for "our boys' does not imply acquiescence to the follies of our leaders, but often quite the reverse.

Christine Fincham

Winchester, Hampshire

• If we have any hopes of a peaceful Olympics in 2012, we shall have to be out of Afghanistan long before.

Peter Moore

Newent, Gloucestershire