When religious leaders, scientists and environmental campaigners from across the world meet to discuss something as controversial as the future of the Mississippi, its delta and the city of New Orleans there are bound to be some cross words.
On the agenda of the symposium starting on Wednesday are the increasing threats of erosion, sea level rise, pollution and storms to the Mississippi basin.
It is part of a wider discussion about climate change and particularly threats to coastal cities like London and New York. The aim by the end of the week is to come to an agreed position and send a forceful message to politicians to act. It is deliberately timed just before the fateful talks in Copenhagen in a month's time which many at the symposium consider will decide the fate of mankind and most species on planet earth.
Ahead of the conference about 50 delegates from Europe and Asia arrived in Memphis on Saturday with the task of educating and updating themselves about the Mississippi.
First on the agenda was a multi-faith service at the Annunciation Christian Orthodox Church led by Metropolitan Nicholas, the Orthodox Bishop of Detroit. It was held at the Orthodox church because the delegates were there at the invitation of the Ecumenical Patriarch Bartholomew, leader of an estimated 300 million Orthodox Christians around the world. When he opens opens the symposium on a riverboat in New Orleans on Wednesday the five days of ethical and scientific debate can begin.
Second visit on Sunday was to Mud Island River Park and the superb museum of the Mississippi history. This sparked a debate about long term consequences of the near 200-year battle of man to contain the river and master its many moods.
Essential stops also included the Cotton Museum of Memphis and the National Civil Rights Museum on the site where Martin Luther King was assassinated. The Rev. Billy Kyles, who was with King when he was shot down was fresh from celebrating 50 years as pastor of Monumental Baptist Church, when he came to show delegates around.
His message was that each generation had to play its part in keeping Martin Luther King's dream alive. "A lesson is that as long as we remained non-violent the world supported us. If we had been shooting or bombing people at random we would have lost the battle."
He said the success of the civil rights movements was more based on the spiritual than the political:
That is why we could endure so much. You knew when you stepped out of church you would be beaten or sitting in the wrong seat in the bus you would be arrested. In the end you knew deep down that you were right and that you would win.
Commenting on the recent taunts again President Obama he said:
We have come a long way, not so long ago it was a criminal offense to teach a slave to read. So to those of us in the movement these outbursts come as no surprise. We knew it was there. I had real concern for his well being during the campaign. But he has hit the ground running and more changes there will be.
Across the lunch table in Memphis on Monday senior scientists and clergy were already debating the practical and ethical issues of whether New Orleans should be rebuilt or whether it should have been the first city in the new age of climate change to retreat inland.
On Wednesday Pastor Kyles should be among the delegates invited by Bartholomew from across the religious spectrum from the US, Europe and Asia. There will also be veterans from previous meetings including the last two symposia in Greenland and the Amazon. Both regions are sending scientists to describe how rapid climate changes in these places are having a direct bearing on the future of the Mississippi basin including the latest figures on rapid sea level rise. Among the audience will also be diehards who still do not want to believe that climate change is real. It should be fun.