Obviously a heated argument but it all comes down to one thing- for UK to remain among the top European players in our out of the EU we have to have a good hub airport . At the moment we have only LHR -LHR can be expanded but LGW Birmingham Manchester etc etc cannot ever become proper hubs because heir just isn't the demand.
So to provide this its is a bigger LHR or Boris Island-and just the fact that the daft bond one supports that idea means it is almost certainly flawed (how many people have died on his stupid bikes without match road changes) . So that leave just LHR-which actually ahs for years and years had a huge empty expanse of land lying just behind the houses and hotels along the Bath Road north of LHR which provides much of the space for a new runway. Ok Sipson has to go but so did the village of Heathrow (for that is where the name comes from) back in 1950 and local people really did live there not the migrant airport workers who comprise the Sipson community of 2015.
As for more planes overflying London well the proposed third runway is located such that a surprising amount of the area beneath the approach at either end is pretty much open too.
Arguments about rail connections are spurious since most go to central London and not anywhere near LHR and as for expanding LGW and linking it to LHR wow that is a good idea- two or three changes of train or a coach round the M25.
No sadly it always had to be LHR all we have done is to waste a fortune on consultants and lawyers and that's a drop in the ocean compared to the cost over runs, crooked deals, environmental surveys etc etc which will mean it costs more for the runway and associated infrastructure than a new airport in most countries.
One bright spot though is despite all that if we do start it we will probably still finish ahead of BBI