(Then again, if Britain was officially part of the US, they may not be imposing martial law in London for the Emperor's visit, what with Constitutional rights and all that. Who was it that said that everyone is either governed by US domestic policy or US foreign policy?)
Ah true; the old divide-and-conquer strategy. Though the US now has Poland and the rest of New Europe to counterbalance the Gaullist menace.
Niall Ferguson, who wrote that book Empire (and a number of others) said that Britain will never leave the EU because its purpose in it is to represent American interests. If it wasn't part of it, who knows what the others would get up to?