Any lingering pretence that David Cameron or George Osborne represent a form of "modern compassionate Conservatism" was finally extinguished by last week's Autumn Statement. They have committed themselves to cutting the state back to the same size as our share of national income as it was 80 years ago – before the NHS and the 1944 Education Act established rights that define us a civilised country.
The Tory project for a second term appears to be born from ideology, not from the necessity of cutting the deficit and balancing the books. Over the days, weeks, and months to come, the Labour Party will have much more to say about the choice facing Britain at the next election as a consequence of this dire economic experiment.
But tomorrow, on the other side of the world, British ministers will be joining negotiations in Lima that can have equally profound consequences for our country and the whole world.
The issue being discussed also symbolises, just as much as the Autumn Statement, Mr Cameron's long retreat from the principles in which he once claimed to believe.
The United Nations climate change talks in Lima ahead of next year's conference in Paris will probably not get the attention they deserve. But they are our best chance yet to secure a binding international agreement to limit greenhouse gas emissions.
They are crucial to anyone who cares about our economic future, the environment our children will inherit, and, as the floods last winter showed, the national security of our country.
Indeed, no amount of promises last week for belated finger-in-the-dyke funding to protect homes can hide how the millions of families in Britain, as well as billions around the world, face an insecure future because of climate change.
Like other EU countries, Britain has signed up for 40 per cent reductions in carbon emissions by 2030. But the leadership and political consensus we once offered the world have been replaced by dither and denial.
In pictures: Changing climate around the world
In pictures: Changing climate around the world
Calved icebergs from the nearby Twin Glaciers are seen floating on the water in Qaqortoq, Greenland
Oroumieh, one of the biggest saltwater lakes on Earth, has shrunk more than 80 percent to 1,000 square kilometers in the past decade. It shrinks mainly because of climate change, expanded irrigation for surrounding farms and the damming of rivers that feed the body of water
A boat navigates among calved icebergs from the nearby Twin Glaciers in Qaqortoq, Greenland. Boats are a crucial mode of transportation in the country that has few roads. As cities like Miami, New York and other vulnerable spots around the world strategize about how to respond to climate change, many Greenlanders simply do what theyve always done: adapt. 'Were used to change, said Greenlander Pilu Neilsen. 'We learn to adapt to whatever comes. If all the glaciers melt, well just get more land
The Svalbard Global Seed Vault is seen after being inaugurated in Longyearbyen, Norway. The 'doomsday' seed vault built to protect millions of food crops from climate change, wars and natural disasters opened deep within an Arctic mountain in the remote Norwegian archipelago of Svalbard
A technician preparing to drain a vast underground lake at the Tete Rousse glacier on the Mont Blanc Alpine mountain, to avert a potentially disatrous flood. Some 65,000 cubic metres (2.3 million cubic feet) of water have gathered in a cavity, dangerously raising the pressure beneath the mountain, a favourite spot for holiday makers in Saint-Gervais-les-Bains
Cracked mud is picture at sunrise in the dried shores of Lake Gruyere affected by continuous drought near the western Switzerland village of Avry-devant-Pont. A leading climate scientist warned that Europe should take action over increasing drought and floods, stressing that some climate change trends were clear despite variations in predictions
Cattle graze on grassland that remains dry and brown at the height of the rainy season in south of Bakersfield, California. Its third straight year of unprecedented drought, California is experiencing its driest year on record, dating back 119 years, and dating back as far as 500 years, according to some scientists who study tree rings
An aerial view shows tents of flood-displaced people surrounded by water in southern Sehwan town. United Nations Framework Convention on Climate Change (UNFCCC) executive secretary Christiana Figueres met with people displaced by last year's devastating floods. Catastrophic monsoon rains that swept through the country in 2010 and affected some 20 million people, destroyed 1.7 million homes and damaged 5.4 million acres of arable land
An aerial view of flooding in North Wagga Wagga. Climate change is amplifying risks from drought, floods, storm and rising seas, threatening all countries but small island states, poor nations and arid regions in particular, UN experts warned
Damages caused by a landslide on the Pan-American highway near La Moramulca, 55 Km south of Tegucigalpa. International highways have been washed out, villages isolated and thousands of families have lost homes and crops in a region that the United Nations has classified as one of the most affected by climate change
A resident sprays water on a peatland fire in Pekanbaru district in Riau province on Indonesia's Sumatra island. Indonesia, an archipelago of 17,000 islands, is one of the world's biggest carbon emitters because of rampant deforestation. US Secretary of State John Kerry Sunday issued a clarion call for nations to do to more to combat climate change, calling it 'the world's largest weapon of mass destruction'
An excavator clearing a peatland forest area for a palm oil plantations in Trumon subdistrict, Aceh province, on Indonesia's Sumatra island. As Southeast Asia's largest economy grows rapidly, swathes of biodiverse forests across the archipelago of 17,000 islands have been cleared to make way for paper and palm oil plantations, as well as for mining and agriculture. The destruction has ravaged biodiversity, placing animals such as orangutans and Sumatran tigers in danger of extinction, while also leading to the release of vast amounts of climate change-causing carbon dioxide
Stagnant rain water with tannery waste make the Hazaribagh area in Old Dhaka as well as Buriganga River the most polluted. Each year during the seven-month long dry season between October and April the Buriganga River becomes totally stagnant with its upstream region drying up and becoming polluted from toxic waste from city industries
Waste water from Dhaka city drained to the River Buriganga contributes to its pollutions. On the World Water Day observed in 2007 under the theme Coping with Water Scarcity, under the leadership of the Food and Agriculture Organization of the United Nations, DrikNEWS explores some of the images of the river. UN-Water has identified coping with water scarcity as part of the strategic issues and priorities requiring joint UN action. The theme highlights the significance of cooperation and importance of an integrated approach to water resource management of water at international, national and local levels
Heavy smog has been lingering in northern and eastern parts of China, disturbing the traffic, worsening air pollution and forcing the closure of schools. China's Environment Ministry said it will send inspection teams to provinces and cities most seriously affected by smog to ensure rules on fighting air pollution are being enforced
When I was in the last Labour Cabinet, I was grateful to both the Tories and the Lib Dems for backing our Climate Change Act. Those were the days when Mr Cameron was busy changing the Conservative Party's logo to a tree, travelling thousands of miles to pose for photo opportunities with a husky on a glacier and promising to lead the "greenest government ever".
Since becoming Prime Minister, however, he has tried to sell off the nation's forests, deterred investment in renewable energy, and declared he wanted rid of "the green crap" altogether.
Ahead of these talks in Lima, the Prime Minister has ignored pleas from the Foreign Office to raise climate change in his recent meetings with Chinese leaders.
But there is a real opportunity to take a decisive step on the path we set out on at the Copenhagen conference in 2009. The United States, the EU and, most importantly, China, are all showing a willingness to act. If negotiations succeed, they will create for the first time a global climate regime for all countries.
From my own experience, I know that the negotiations are difficult: you need clear principles and there must be real diplomatic engagement including a willingness to listen to other countries' views.
So if I were Prime Minister, here is what I would do.
First, we would seek to raise our ambition to meet the scale of the challenge. In the past five years, the scientific evidence of climate change has got stronger, not weaker, even as the Government has allowed the political consensus around action in the UK to fray. In Lima next week and in Paris next year, a Labour government would be pushing for global targets for reducing carbon emissions that rise every five years with regular reviews towards the long-term goal of what the science now tells us is necessary – zero net global emissions in the latter half of this century.
Second, we would engage through every diplomatic channel and at every opportunity to ensure the whole world faces up to this great threat hanging over humanity. We would demand that climate change is on the agenda of every international summit in the run-up to Paris. And leaders visiting Britain during the next government can be certain that action on climate change will always be on the agenda.
Third, we would lead by example, not follow in the wake of others. Under the last Labour government, Britain was the first country in the world to enshrine a long-term emissions target into law. Under the next Labour government, we will commit Britain to making our electricity supply carbon free by 2030.
Fourth, we will not make the economy an excuse for dragging our feet on climate change. That there was no mention of climate change in the Chancellor's Autumn Statement tells you all you need to know about where this issue now sits in the Government's priorities.
There is no trade-off between building a recovery which works for most people and resetting the energy market to keep household bills low, creating new high-skill, high-wage jobs which can help to pay down the deficit, or investing in green technology which can power Britain's economy forward into the future.
The last Labour government helped to create new markets for thousands of British companies and more than a million new jobs in the green sector. This Government has sabotaged new investment through a combination of uncertainty and internal Tory party politics where too many of its MPs are flirting with climate change denial.
My goal is to have the ambition matched with certainty for Britain to be a world leader in green technology by 2025, creating another one million new jobs.
The environment may not be as fashionable an issue now as it was when David Cameron attached a wind turbine to his house. But I believe tackling climate change is the most important thing I can do in politics for the long-term future of my kids and their generation.
And I will not leave those principles behind at the door to Downing Street. That is the choice the country will face at the next election. A Conservative government that abdicates its responsibilities and makes Britain a laggard on climate change. Or a Labour government that leads.
Ed Miliband is the leader of the Labour Party