One of the Tories' favourite stories is about a note left by the former Chief Secretary to the Treasury, Liam Byrne, after Labour were ejected from office and the coalition took over in 2010. The single sentence, 'I'm afraid there is no money', was deemed to be of such worth that David Cameron paraded a photocopy of the letter around in the 2015 General Election. The point they're trying to prove is simple: Labour can't be trusted with your money, and only the Tories will manage the finances with the prudence required.
More than seven years after that note was written and the Tories claims to be the party of careful financial management have fallen apart. Not only have we missed every election target they set on reducing the debt and deficit, but the spending choices made by ministers have been disastrous. Savings have been made, by slashing spending on local authorities and freezing benefits and capping public sector pay rises. At the same time we've seen corporate taxes slashed - with the aim of making Britain into a haven for companies who want to contribute as little as possible to the country in which they operate.
Public sector cuts and corporate tax giveaways might be both callous and economically illiterate, but they are, to some extent, what you'd expect from a party with a history of backing big money. Some of the Government's other spending decisions are, however, harder to explain.
Take the purchase of the F-35 Lightning II - a next generation warplane that is set to cost the Government £150million a pop, despite multiple failings exposed just this week. These jets, which were originally set to cost far less, are designed to take off and land vertically - but a recent expose by the Times has shown that four of those already purchased are actually too heavy to perform this function. Add to this major communications problems with the planes, night-vision failures and a software system vulnerable to cyber attack, and it's clear that we're ploughing billions into an incredibly risky project. Britain is set to spend £12billion on the new jets and aircraft carriers by 2021, and there's a very real chance that they won't be fully operational.
Of all of the mega-projects, it is the renewal of Trident that is potentially the most catastrophic. We're set to spend over £100billion on a weapon that makes us less safe, not more, at the very same time as nurses and firefighters are being told that they can't have pay rise because such a move would risk the country's finances. The arguments against Trident are well-rehearsed. But the very fact that building a new generation of weapons of mass destruction is pitched by politicians as central to our nationhood should give us pause for thought. What makes Britain need nukes so desperately when almost all other countries on earth maintain their safety without them?
Perhaps the most surprising spending commitment by this Government (and indeed by the Labour Party) is on HS2. The scheme could cost up to £104billion in total, including extensions to Manchester and Leeds. According to transport expert Michael Byng, the first 6.6miles from Euston to Old Oak Common would cost £8.25billion, or £1.25billion a mile. The line will shave minutes off journeys to London while channelling funding away from where it's really needed - providing people with improved local rail connections between our towns and cities across the country.
Any claim the Tories might have had to be the party of sound finances has demonstrably fallen by the wayside. The country is being run by a group of Ministers who are willing to flush billions down the drain on projects we don't need, while refusing to support the social infrastructure that's needed to keep this country's social fabric from being ripped apart. At a time when we should be diverting every available resource towards building a zero-carbon economy, we see support for renewables and energy efficiency stalling. If we were to divert cash away from these overprices vanity projects and into building an economy fit for the future, we'd quickly be world-leaders for all the right reasons.
My challenge to both the Tories and the Official Opposition is simple: let's think again before we plough ahead with these projects. We're a small country that should be bold in its ambition, but not reliant on megaprojects to show the strength of a Government.
Britain has a chance to build an economy that not only meets the challenges of the 21st Century head-on but creates a better country in the process. We can do without overpriced fighter jets, nuclear weapons and HS2 - let's not miss this opportunity.
Caroline Lucas is co-leader of the Green Party and MP for Brighton Pavilion