By Bridget Kendall BBC diplomatic correspondent

Ten years out of power, and just turned 71, Mikhail Gorbachev was as energetic as ever.

He arrived at our Moscow Bureau ahead of time, straight off the plane from Austria.

If only I hadn't gone on holiday that August... if I hadn't gone, if I'd stayed in Moscow all summer, then nothing would have happened

Gorbachev on the 1991 coup

The idea of an internet forum, 700 questions from all over the world, instantly intrigued him:

"Nowadays we are all linked by technology," he mused as we pinned on a microphone, "but think how dependent we are all becoming on it".

"These are the dangers that threaten our societies as we brace ourselves for more terrorism," he added.

Words for Bush

But it was the war on terrorism and the Bush administration's plan for a possible Phase Two against Iraq and other countries harbouring weapons of mass destruction that prompted his strongest comments.

The circumstances of his fall from power clearly haunt him

An e-mailer from Karachi wanted to know: What did he think of President Bush's current policy on terrorism?

Mr Gorbachev conceded that the war in Afghanistan had been necessary, but what about what came afterwards? He almost banged the table as he launched into full flow about George W Bush's "axis of evil".

"The Americans' quick victory in Afghanistan has blinded them to the fact you can't win this battle with one quick hit, one rocket burst," he said.

But what seemed to make him even more incensed were the recent hints from US officials that Washington was prepared to go it alone against Iraq, even without the approval of the United Nations or other allies.

"This is a return to the Cold War," he said, "a return to Cold War thinking and methods."

Off camera, though, Mr Gorbachev was a bit more complimentary about the American president. He had met him as a much younger man, he said, when his dad was president. And on the whole, said Mr Gorbachev, he seemed to be doing okay.

Reflecting on his downfall

Many people wanted insights into his time in office as Soviet leader, and the abortive coup and collapse of the Soviet Union that ended it.

The pain doesn't go away. That's why I travel a lot and work hard, to keep myself busy

Gorbachev on his wife's death

But when one man from Antigua declared he thought Mr Gorbachev ought to take the blame for what had gone wrong, the former Kremlin leader vigorously defended himself.

But the dramatic events of August 1991, when members of his own government imprisoned him in his Crimean dacha, obviously continue to haunt him.

And he came out with an intriguing new slant on what happened.

As we ended the interview he leant across and touched my arm: "If only I hadn't gone on holiday that August," he said. "I was exhausted and I thought, 'I only need ten days' rest'. I was so tired. But if I hadn't gone, if I'd stayed in Moscow all summer, then nothing would have happened. That's how small things influence history."

Memories of Raisa

There was one other touching personal insight when he spoke about his wife Raisa, who died two years ago from leukaemia.

Gorbachev spoke movingly of his love for Raisa

It was the recognition of their long and close relationship - they met as teenagers - that made many Russians start to re-evaluate their former president. As he spoke of her, tears welled up in his eyes.

"The pain doesn't go away. That's why I travel a lot and work hard, to keep myself busy. It was my birthday recently, and what did I do? I went to the cemetery to put her favourite flowers on her grave. It is lonely."

Affable

After the web cast, as he prepared to leave, it was interesting how many of the younger people in the office wanted to have their photos taken with him - youngsters in their 20s who even 10 years ago would have been barely aware of him.

He good-naturedly obliged, making a joke of it, ensuring no one was left out.

"Cheese!" he said in English, as he smiled for another photograph, adding in Russian, "You see, I do know some English!"

Hard to believe this man had once been the most powerful man in the Soviet Union: the terrifying, unapproachable general secretary of the Politburo, cut off from ordinary people, cocooned in the grandeur of the Kremlin.

This is a man who gave away absolute power, and made his vast country seem less threatening. He still seems convinced it was all worth it.