Yesterday was the second anniversary of the day Hurricane Katrina came screaming in from the sea and changed everyone's lives forever.

President Bush was in town to commemorate that terrible day, and he opened a school a couple of miles down the road from here. All morning, helicopters buzzed back and forth above our heads.

I watched him on TV giving a speech in a classroom, surrounded by black children in red uniforms. It was a pathetic performance: rambling, uncharismatic, more of an impromptu chat than an oration.

He had a card in his hand with some statistics on it - billions of dollars spent on rebuilding levees, schools reopened, that kind of thing - and whenever he started running out of ideas, he would glance down and read out another figure. Whatever the reasons he was elected, it wasn't for his oratory.

In the evening, Pam and I went to a candlelit vigil in Jackson Square, in front of the lovely black-and-white Disneyland-style cathedral that dominates the view from the river.

We listened to mayor Ray Nagin, a figure only marginally less unpopular in these parts than President Bush. He was widely criticised for dithering when it came to ordering an evacuation - though if one of the most destructive hurricanes in history was making a beeline for me, I wouldn't hang around for instructions from some politician.

Nagin told us how, on the day after Katrina, he had taken a helicopter for a tour of inspection. He was very keen to emphasise that this was not some cheapskate chartered chopper, but a Black Hawk, a deadly airborne arsenal of the kind used to pacify restless natives in Somalia.

A sign-language interpreter stood beside him, and I was hypnotised by her expressive gestures. Every now and then I could recognise a word. To say 'helicopter', she made a T of her hands, then wiggled her fingers in a semblance of rotors.

'We flew out across the northern suburbs, and saw a terrible trail of destruction,' Nagin told us. 'Then I asked the pilot to swing back here, back towards the cathedral and the Mississippi. I saw Jackson Square gleaming in the sunshine, and it was like a picture postcard.'

He was doing so well, and then, with a few ill-chosen words, he lost all my sympathy and I found it hard to keep a straight face.

'Right there, in that Black Hawk helicopter, I heard the voice of God speaking to me. He said: "Do you see that square and that cathedral? I shall spare them, so that the city of New Orleans may rise again and make a fresh start"'.

I was very taken with this image, a man with such delusions of grandeur that he had a hotline to the Supreme Being from his rotary-winged Noah's Ark. And I couldn't help wondering irreverently why God had decided to spare Bourbon Street, that great den of drink-sodden debauchery just two blocks away.

But all was not lost. Suddenly we were hearing from a string of prominent Southern preachers, including legendary civil rights activist Al Sharpton, and the mood of the crowd changed dramatically. They were electrified, as one voice after another rose in impassioned condemnation of the bedrock of injustice lying just beneath the topsoil of American society until Katrina laid it bare.

The speakers told us to yell out the names of people we knew who had died or been displaced, our hopes for the future of New Orleans and the Gulf Coast, and how we would help to make it a better place. And we did.

Walking sombrely home, we talked about the art of speechmaking. Listening to Bush and Nagin had been a depressing experience: no fire, no passion, precious little sincerity. But it was good to know that in churches and chapels up and down the land, people could still stand up and send shivers down others' spines with a few well-crafted sentences.