Re: US/UK dual citizenship - passport misery
The misunderstanding your friend had is clear from the title of this thread - in the eyes of the US, there's no such thing as dual nationality. If you have an American passport, you renounce any other citizenship. And if you fly on an international flight as a US citizen, you are required to have a US passport (some NA countries excepted). A British (or any other) passport is not recognised by the US authorities if you are a US citizen.
The problem is that the opposite isn't true - the UK and some other Eu. countries have no problem with dual nationality so it's perfectly OK to have an Eu. and US passport. Just be aware that the US, and US airlines, don't see it that way.