I WAS sorry to see my fellow Scot, Colin Powell, resign from the State Department yesterday. Yes, he is part Scottish.

It is fashionable in these parts to be rude about Mr Powell, as you might expect with someone who was everybody's darling when he came into office.

The world - wrongly, in my opinion - saw him as the prefect sent on a school trip to make sure all the naughty boys and girls, from the president on down, behaved. And everyone likes to see the head boy fall, so it was no surprise when every bad policy decision was laid at his doorstep. In truth, he served out of a sense of duty not to the world, but to Mr Bush and the Republican Party. He is, after all, a member of the party in power, just like his fellow moderate John McCain, who went out to bat for Mr Bush despite having had his sterling war record dragged through the mud by the president's people four years ago.

Why didn't Mr Powell resign in anger? It was a question that many journalists who spent endless days and nights travelling with Mr Powell, as I did, would ask themselves in the back of his plane. Was he sticking around because he wanted to make a difference? If so, his opinions were being ignored. From his visit to Yasser Arafat's besieged compound in Ramallah in 2002, when his Pentagon rivals back in Washington so undermined him that the Palestinians were likelier to convert to Judaism than call off the intifadah, to his attempts to keep talking to North Korea, his efforts to sustain a foreign policy in the mainstream tradition of the first President Bush failed.

Sometimes he was a Trojan horse, the multilateralist sent to convince his foreign counterparts of the wisdom of Mr Bush's more unpopular decisions. Other times, we imagined he was a dragon slayer who fought back the fire-breathing hawks. The press had heroic fantasies for his time in office, imagining he could somehow stop the war in Iraq, or puncture Mr Bush's "axis of evil" mentality, or conjure up an Israeli-Palestinian peace deal.

Perhaps it was lack of sleep, for Mr Powell never liked to travel, and cut his trips as short as he possibly could. I remember a particularly exhausting tour to Asia which traditionally, at least in Madeleine Albright's tenure, would have ended with an overnight in Hawaii at a hotel with a spa so fabulous that even the thought of it made ten days of three hours' sleep a night quite bearable. Mr Powell scrapped the overnight at the last minute. We forgave him for that, but not for failing to produce the earth-shattering headlines we dreamt of.