Patrick Cockburn: To achieve peace, we must break the Taliban's support base in Pakistan

Afghans wonder if we are really prepared to do anything effective about Pakistan

Hamid Karzai, who played host to Gordon Brown in Kabul yesterday, will have been delighted to hear the Prime Minister confirm the long-standing Afghan belief that there can be no long-term success against the Taliban in southern Afghanistan so long as they base themselves in Pakistan.

Afghan leaders blame the Taliban resurgence since 2006 on support from the ISI, Pakistan's military intelligence, and the use of base areas in Pakistan to regroup, train, and receive weapons and supplies. But Afghans wonder if the US, Britain or their allies are really prepared to do anything effective about Pakistan's support for the Taliban, which has been obvious since the 1990s.

The lockdown in Kabul ahead of Mr Brown's visit with checkpoints and road closures was an illustration of the security problem which still plagues the country.

The Afghan Army and police are also keen to make sure that Afghan Independence Day passes off peacefully, in contrast to last year, when Taliban gunmen tried to shoot the Afghan President during the ceremonies.

This year, suicide bombers have so far had more difficulty in penetrating central Kabul, although there was one attack on the Justice Ministry and the the Prisons Administration.

The most serious deterioration in security in the last year has been on the roads leading from Kabul. "A year ago I was able to go to my village in Logar province 60 miles south of Kabul, but now I would not dare go because the Taliban would kill me for having links with the government," said one Afghan journalist, who did not want his name published.

"Groups of six or eight Taliban, riding motorcycles, set up mobile checkpoints and look for government employees or people connected with non-government organisations. If they find them, they shoot them."

Despite Mr Brown's tough words, the ability of the Taliban to control or contest almost all of southern Afghanistan outside the cities will be difficult to reverse. Britain had 8,300 troops in Afghanistan, mostly in Helmand, and is sending a further 700 for the elections in August. They will be reinforced by more than 8,000 US Marines in the coming weeks, which are part of the extra 25,000 US soldiers that President Obama is sending to reinforce the 40,000 already in the country.

"We are confident that we are shouldering our share of the burden," Mr Brown said.

The only safe road out of Kabul is to the north, through the Salang tunnel, eventually leading to Tajikistan and Uzbekistan. This route is likely to be used increasingly for US and Nato supplies. which are being threatened by repeated attacks on vehicles carrying them through Peshawar in Pakistan.

All other roads around the capital are permanently or intermittently under Taliban control. The father of the Education Minister was recently kidnapped when he went to attend a family funeral in his home province.

Officials travelling with Mr Brown said he is to unveil a new strategy similar to that of President Obama, which will put emphasis on training police as well as the army. The former, paid only £50 a month, are notoriously corrupt and ineffective. The regular army has a much better reputation among Afghans but is poorly equipped, its soldiers often driving thin skinned vehicles that are highly vulnerable to bomb attacks.