Why are the USA blaming the UK for the Gulf oil spill?

I’ve been led to believe that the platform was managed by Americans and crewed by Americans.
OK the platform is owned by BP but this is the same BP that was until rebranding in 2000 BP AMOCO (AMerican Oil COmpany).
I also understand that BP WILL stay and clear up even setting up a fund to compensate people put out by this disaster, which is a damn site more than Union Carbide did in India 26 years ago after their gas plant leaked and killed an estimated 25000 Indians.
This Bhopal disaster is still causing casualties today and I also believe that an arrest warrant still stands for the CEO Warren Anderson in India.

Is this just a question of location?
What would have happened if this disaster had happened in the USA and killed 25000 US citizens?

It’s all very good wagging fingers at other people/countries/companies but before you do check your own history first.