Unlike our opponents, the Lib Dems have been united against Heathrow expansion for a generation. Here’s why.
The Liberal Democrats have opposed Heathrow expansion for a generation. My entire party - from the leadership to the MPs to the membership - is united.
At every opportunity the Liberal Democrats have had to cast a vote at this - on a local level, at a London level, in the Parliamentary select committee - it has always been, and will always be, a firm NO to any expansion at that airport.
My Liberal Democrat colleagues who served in the Government insisted our Heathrow policy was written into the Coalition Agreement in 2010. And they refused to countenance any attempts by the Conservatives in government to renege on that agreement.
725,000 people live under the Heathrow flight path, and that is before any expansion at Heathrow is considered.
240,000 people live within the "57LAeq contour" which means they experience persistent and high levels of noise from aircraft noise, according to the World Health Organisation and the European Commission. No airport in Europe comes even close to that level of noise pollution.
The roads around Heathrow are so polluted that they are going to be illegal under European air quality legislation even without any expansion. Those same roads are also incredibly congested, some of the worst in London.
However quiet planes get, they are still noisy. However safe planes get, they are still flying above an extraordinarily densely populated chunk of residential London.
People close to the airport are known to suffer health problems and high levels of stress and anxiety due to exposure throughout the day from aircraft noise. Thousands of people living under the flight path are woken up before 5am.
So, the airport is big enough. There is no connectivity crisis - London is widely regarded as one of the best connected cities in the world with its five airports well serving around 130 million passengers a year. This is more than any other city worldwide.
For all these reasons, the Liberal Democrats have again in our 2015 manifesto ruled out the expansion of Heathrow. You can read about the alternative approach to aviation which we have set out, here:
In marked contrast, it has caused considerable consternation locally that the Conservative manifesto for 2015 has dropped opposition to Heathrow expansion. This has put the Conservative candidate, Zac Goldsmith, in a very difficult position – it’s the precise circumstance he has previously said would be unacceptable to him as an opponent of Heathrow expansion. In 2012, quite separate from this threat to trigger a by-election if Heathrow is green-lit by Tories, he said unambiguously:
"I would not stand as a Conservative if the Conservatives allow room for a third runway in their manifesto."
I’ve always thought that the reason why he went out on a limb like that back in 2012 was because he expected to be able to use his threat of not standing for the Tories as leverage internally within his party to get them to rule out Heathrow expansion in the manifesto. His failure to achieve this shows the limited influence he has had on his party over the past five years – they have called his bluff and he has not followed through with his threat.
In recent days, Mr Goldsmith has repeatedly failed to explain away his breaking of that commitment to residents, tortuously trying to claim that it is somehow the fault of the Liberal Democrats that his own party, the Conservatives, has now dropped its opposition to Heathrow expansion.
Do not just take it from me - the Conservative party chairman, Grant Shapps, says explicitly that Tory ministers in a future government must give Heathrow the go-ahead if that's what the Davies Commission recommends.
The report of the Davies Commission was set up at the direct insistence of George Osborne and David Cameron to prepare the Tories for dropping their anti-expansion policy. It is not some sort of biblical tablet of stone which everyone has to sign up to.
All political parties had the chance to seek a fresh electoral mandate in their manifestos opposing Heathrow expansion rather than tying themselves to the Davies Commission.
The Liberal Democrats are seeking that mandate at this election; the Conservatives have chosen not to.
Mr Goldsmith knows he would be no brake on a Conservative government intent on expanding Heathrow. It needs the Liberal Democrats, a party united in opposition to Heathrow expansion, to once again stop this environmental outrage from happening.
With your support, the Liberal Democrats will be able to continue to keep Heathrow expansion off the agenda, for good.