1. BP was in control of the rig, and made the decisions. The people from Transocean were ignored.
2. It is not as if this were the first time BP cut corners on safety, with disastrous effects. Cutting corners on safety is its modus operandi. This has been notoriously so for years, BP unquestionably has the worst corporate culture of any of the oil majors. Exxon had a big oil spill, cleaned up its act, and has little trouble since. It has become the best run of the major oil companies.
3. Brown, the old CEO of BP, expanded by buying up competitors and cutting costs--notably safety, relentlessly. Then came the Texas City explosion. Tony Hayward, when he took over, said words to the effect safety would be his number one priority. He didn't. There were additional, ongoing spills in Alaska.
4. I do not know which, if any, American companies have rigs in the North Sea, but would think that if Americans had a really bad oil spill there and destroyed the coast of Scotland, the Brits would have harsh things to say about that firm. And I would not necessarily attribute that to bigotry,