The conventional scapegoat for all this is an extremist and incompetent American administration, to which our prime minister has foolishly hitched his policy. I think this is only part of the story: the malaise is deeper. My own experience of making and effecting policy in these areas is that the system itself is bust - not fit for purpose. And in allowing it to continue in its current form, we the public are also culpable. Through habit and traditional deference to the foreign-policy elite, we permit these mistakes in our name.

The abiding feature of foreign-policy making is its closed, secretive and circumscribed nature. Information is reduced and filtered to a very small group of people, these days concentrated mainly in No 10, who make decisions based on abstractions many removes distant from reality. Even on the ground, the strictures of security prevent diplomats from all but the briefest contact with the everyday reality of Afghans and Iraqis.

When I helped negotiate UN security council resolutions on Iraq, I claimed knowledge of that country - from reports, intelligence and so forth - but with no experience whatsoever of the place itself, its air, its people, its reality. After the invasion of Afghanistan, when I was posted to Kabul, I found myself writing reports about the "political situation" in Afghanistan based on brief forays outside the high embassy walls for meetings surrounded by bodyguards with sympathetic Afghans, conducted through interpreters. I may as well have been a Pashtun trying to understand the Highlands of Scotland without English.

I did my best, but the temptation is strong and irresistible to bend this scant knowledge to our preferred version of events - for instance that Afghans want democracy (when in fact their overriding message, still not fully heard, is the desire for security, development and freedom from the warlords, many of whom we helped place in power). Back in the capital, greater is the need for officials and ministers to reassure the public that they understand what is "really" going on in Iraq or Afghanistan. Officials rush about, ever more busily feeding the machine of endless meetings and briefings, but with all too little time to stop and think. Even the press prefer western "experts", usually located thousands of miles distant, to explain these places, rather than those with most at stake. We all love to project our own designs and prejudices on the distant "other".

We are stuck in old habits of making and talking about foreign policy. We want our diplomats and ministers to take care of the world, so we can get on with our lives. This is an unaffordable luxury. In the 21st century, everything and everyone is connected - whether climate change or violence in Somalia, which can through myriad paths contribute to terror attacks in London. In international forums, diplomats are arbitrating more and more of our business, while we have little or no idea of what they are doing, or even who they are. The existing mechanisms of scrutiny leave much to be desired. In parliament, no one reads the toothless reports of the foreign affairs committee, which is led by a government loyalist. Full debates, even when so rarely permitted, are a party political knockabout.

Consideration of foreign policy needs to find much more room for the reality of those affected by our decisions. Only they can speak with authority on what is "really" going on in their countries. As I found in my work at the UN security council, all too often they are left out. At the other end, there must be more consultation of those in whose name policy is made: us, the public. This is not just an idealistic call for more accountability and democracy in foreign policy, it is deeply practical. We cannot always know what policy is right, what is really going on. Only through the closest possible encounter with the facts - the people - on the ground, through open debate, through scrutiny, can we hope to make better decisions in future.

· Carne Ross is the director of Independent Diplomat, a non-profit diplomatic advisory group; his book, Independent Diplomat: Dispatches from an Unaccountable Elite, is published next week

info@independentdiplomat.com