It's in 1 of it's natural beds, the problem is they've been trying to keep it there while it wants to go spend a weekend (or a millennium) at one of its other places.
Yes, I know, but the operative term here, as you know, is "1 of its natural beds". I'm not an expert on the Mississippi by any stretch of the imagination, but I have read that long before the Corps of Engineers started forcing the river to follow its current course, it would occasionally re-direct itself to flow through Lafayette or Lake Charles or somplace like that. Considering that the lower part of the La. peninsula is slowly being consumed by the Gulf of Mexico (according to a recent article), it begs the question of whether or not it is worth the time and money to maintain the existing levy system for the river AND to rebuild New Orleans.
Both of those things have romantic, sentimental and historical symbolism but, from a practicality standpoint, they don't make a lot of sense.