Why does Boris Johnson persist in his dog & bone pursuit of the Thames Estuary airport?

This issue has been the subject of repeated feasibility studies, Enquiries. Discussions Objections over many years and has always been rejected mainly on environmental issues It will NEVER happen. Fact is if the latest EU proposal to increase the cost of air travel coupled with fuel cost perhaps Headcorn airfield kent will be large enough to cope with those people lucky enough to be able to afford to fly.LOL.