The reason that (non-airline) public transport across the US is so bad is at least in part because the oil companies bought up city transit corporations to get them to fold, so that the car could reign supreme. The petrol price in the US also completely ignores the environmental impact - which biases everything even more heavily to the car.
I agree strongly that where surface public transport is a viable option, it ought to receive investment priority. Unfortunately, the UK govt is uninterested in investing public money in such projects.
In particular, I am amazed that anybody should fly to Brussels or Paris from London, given the public transport links even in their current state. But then, I understand that MEP's receive an allowance of £500 per flight taken on euro-business, regardless of the amount they pay for their ticket, so I guess that a lot of pointless flights are inevitable.
I also know that I'd rather live 10 miles from Heathrow on an approach or departure route than any distance from a railway station within 300 metres of the railway. Planning blight for a railway is considerably worse than that for an airport, and improvements in technology don't generally decrease noise along a railway line.