He was at his desk at the Pentagon on 9/11. As the chaos unfolded, he refused to leave

Matthew Klimow recalls the day a hijacked airliner crashed into the headquarters of the US defence department in Arlington, Virginia

All day I had been a good soldier: stolid, resolute, unemotional, rational, and dispassionate," writes Matthew Klimow, recalling the wave of emotion that overwhelmed him as he arrived home from the Pentagon on 11 September 2001. There was sadness for the lives lost. But there was another emotion, too: humiliation.

We, as a nation, had been humbled," writes the retired army colonel, who remained at the Pentagon even after it was struck by a hijacked airliner, killing all 64 people onboard and 125 inside the building. The fighting force of which I was part had been impotent, unable to protect our fellow citizens. The darkness I felt matched the darkness inside my house as I opened the door."