The usual understanding of a "disaster" is that things go really wrong. You know, someone swims happily at the beach and is then caught by the undercurrent, and what was long, calm strokes indicates that the person is about to drown. So, you swim to the person, offer a hand just to find this going for a book, looking for the legal terms and demanding to be saved by someone in particular and according to special terms.
Dredging giant’s offer to help with oil slick turned down due to US Jones Act
(You have to be a subscriber to Lloyds List to read it all - but it is the site about all shipping news in the world, not just in the US.)
This "Jones Act" will now cost the Americans a lot, most likely a better part of the 20 billion in the escrow account. Simply because help was offer, but this was turned down as "not good enough".
So, to claim "disaster" you must be willing to receive help, or allow us to call you "Lazy, hypocritical arrogant twats" - and "us" include BP. Lloyds terms for salvage, is complete surrender of the vessel.