"We know that Pakistan matters not just because it is the location for the Afghanistan Taliban leadership; it's also important in its own right. It's the base for al Qaeda, it's a nuclear weapons state with the long-term risk of radicalisation," Miliband said in his testimony before the Senate Foreign Relations Committee, which had convened a special hearing on Afghanistan and Pakistan.
"I believe that the last year has shown a major change in approach from the Afghan civilian and military leadership, recognising the mortal threat that's posed to the Pakistani state from within its own borders," he told the Senators at the meeting chaired by Senator John Kerry.
"The strategic reorientation of Pakistan has some way to go, but I believe that the efforts that are being made now in South Waziristan show the level of commitment that the Pakistani authorities are willing to devote to what is a long-term struggle for the survival of that country," he said.
Miliband said Britain believes that there is a real possibility of developing shared interests between the neighbors of Afghanistan and Afghanistan itself, founded on a commitment to respect the sovereignty and independence of Afghanistan.
Noting that the primary security challenge being faced is that of international terrorism, Miliband said in terms of territorial integrity as a country, Britain has rarely been safer.
"We also know that 70 per cent of the terrorist plots that are aimed at the United Kingdom can trace their links back to the badlands of the Afghan-Pakistan border. So we have a very clear national security interest there," he argued.
"We know from the 1990s that Afghanistan is the incubator of choice for global jihad for al-Qaeda. We know that the Taliban government of the 1990s provided -- sponsored -- provided a supportive environment and sponsored al Qaeda's development within its own borders," he said.
"So for those reasons, I feel confident in saying to the British people that we would not risk our -- the lives and welfare of our armed forces, but also our diplomats and our aid workers, if our national security was not at stake, but we believe it's very important that the insurgency that threatens the country of Afghanistan is not allowed again to provide an umbrella to al Qaeda," Miliband said.
"We know too that al-Qaeda senior leadership is based on the Pakistan side of the border. That does not, in my view, invalidate the campaign in Afghanistan. What it does is emphasize the interdependence between stability in Afghanistan and stability in Pakistan," he said.
For the first time in a very long time, there is complementary military pressure on both sides of the Durand Line, the 1,600-mile border that exists between Afghanistan and Pakistan, said the British Foreign Secretary.
"The losses that are being suffered by the Pakistani army and people on the Pakistani side of the border are testimony to the fact that the insurgency understands the significance of that line and that it understands the significance of the campaign on both sides of the border," he said.
"So we have a difficult and complicated argument to put to our people, but it's one that speaks to the nature of national insecurity in the modern world, and that's the basis on which we try to prosecute our case," he added.