It is really disappointing that the debate about aviation capacity in the South East has become about Boris Island versus an additional runway at Heathrow. The issues about the provision of capacity and how best to deliver it generate many more options. This is a debate which needs to be conducted in the interests of Great Britain PLC. Sadly it seems to be more influenced by those who live under the Heathrow flightpath and those who are so scared of airport expansion anywhere near their own backyard they somehow think that plonking an airport in the middle of the Thames Estuary is the magic solution. It really isn't any kind of solution at all. It completely ignores the prospects afforded by expanding other airports in the South East; it completely ignores the economic consequences for West London and it completely ignores the economics of the Thames.

Before settling on where future capacity should be we need to settle exactly what we are trying to achieve. Firstly, do we need a four runway airport hub? Or can we achieve the benefits of hubbing as some have suggested by enhanced connectivity between our existing airport infrastructure?

I tend to be persuaded by the arguments in favour of a single hub - we don't want our wealth creators skipping between numerous connections to generate business for us. However, whilst I am persuaded, the case is not yet compelling. It has to be acknowledged that high speed rail and investment in CrossRail do open up the opportunity for greater connectivity between our airports. I think much more has to be done to make the case that enhanced connectivity will not deliver the kind of capacity expansion we need to maintain our competitiveness. If the decision is taken for a the development of a new hub to replace Heathrow, this will necessitate many billions of public spending and we need to be sure that such expenditure does offer value for money for the taxpayer.

Personally I have always supported expansion at Heathrow. Whilst you might not build a new airport there today, the fact is it is what it is. Heathrow is our international hub airport and one of the most successful in the world. Its proximity to London and the ability to connect across the world has made it an attractive location for business. One need only drive down the A4 and see the international corporate offices on either side of the road to see that Heathrow has added to the attraction of London and the UK as the place to headquarter European operations.

Opponents of Heathrow expansion cite the environmental consequences, but rather less thought has been given to the economic consequences. So if the UK is to build a brand new four runway airport it needs to give very careful consideration to the economic consequences for London.

But let us say for the sake of argument that we have proved that we cant deliver what we need through improved connectivity; and we are so convinced against expansion at Heathrow that we need to develop a new four runway hub.

You have to hand it to Boris. In his populist way he has managed to turn a half-baked proposal for an airport in the Thames Estuary into the only show in town. It is not.

There have been numerous proposals for an airport in the Thames Estuary over many decades. At my last count I came to eight different locations. Wind, fog and risk of birdstrike raise safety issues and as has been considered many times, the location would require investment of many billions.

And before anyone accuses me of being a nimby, I should add that none of those locations are nearer to me than the current London City airport. What I do represent however is a considerable amount of port activity. Notwithstanding Boris's protestations that the docks have gone from the Thames - they have not - they have shifted East. We still have more tonnage landed in the Port of London than Dover and Liverpool and all the famous ports. And that is increasing with new capacity at Tilbury and Purfleet, not mention the brand new London Gateway which will handle the World's biggest ships and will become the hub Port for the nation. The Thames is our port hub. The airport hub should go somewhere else.

So where? Well, what Boris does have a point about is his view that more needs to be done to strengthen the economy to the East of London and unlock new job potential. And infrastructure to the east would secure that. So it is very surprising that so little attention consideration has been given to the opportunities afforded by expansion at Stansted.

When all things are considered Stansted is the obvious place. It sits at a convenient point on the road network. There would need to be investment in additional road and transport infrastructure, but this would be to the benefit of the whole of East Anglia and indeed London as it would make life so much easier for the many commuters heading into the capital from the East. And it is the place where the construction of new runways would have least environmental impact.

So the case for Stansted is strong. There is a risk that by forcing BAA to sell this may close this option down. If Ryanair buys it will only be interested in ownership as a way of reducing the cost of operating its own flights. It is one thing the Competition Commission attacking BAA's monopoly but I hope it will be mindful of the competition implications of a key airport being captured by an airline.

The time has come for a mature and informed debate about where airport expansion should take place. It is time for leadership in the interest of UK PLC and it is time for politicians to stop running scared of nimbyism and to show that leadership.