It's very easy to want to assign blame in these situations (heck, I have in previous posts, in some cases somewhat unfairly...)
Here is a really good analysis of the situation. Easily the best (and most objective) that I have read thus far:
http://news.bbc.co.uk/2/hi/americas/4216508.stmAnyone get the feeling that by the time the investigation is done, the report is going to be thick enough to dam one of the levees?