What you basically say is, that the
only mainstream currency is the USD, which, i think, is kinda wrong.
Bitcoin is more than just a currency though, it's also a payment system.
There's no way we can convince/force OPEC to accept bitcoins,
Saddam tried to sell his oil for EUR once and we all know what happened to him.
But you know what? We don't have to, all they need is a BitPay account.