I think that was his point Whickerman, he was using the economy as a justification againt environmental concerns regarding airport expansion.
The woman from Oxford University's climate research unit then totally whipped the legs out from under him by pointing out that for every �1 spent in the UK by foreign tourists, UK tourists spent �2.30 abroad.
What does it mean to "diversify the economy", firstly if your job depends on tourism, and secondly if your country has already "diversified" into tourism?