Well, we can now look forward to Boris Johnson lying down in front of the digger.
However, it must have been obvious long ago that an airport near Hounslow was in a totally inappropriate location. A national hub airport is a necessity. I also recall much discussion in 1964/5 about a third London Airport - Wing and Cublington and Maplin Sands were all in contention but it was decided to expand Stansted. I did think that Boris Johnson's campaign for an airport in the Thames Estuary had a lot to commend it.
The japanese were forced to build a new airport for Tokyo. They built it at Narita about 50 miles from central Tokyo. And the new airport to serve Osaka and Kobe was built on an artificial island in Osaka Bay. It is called Kansai to reflect its regional role.