Brexit offers an unprecedented opportunity to redesign UK food systems, and the relationship between farmers and consumers, the food industry, landscape, and nature itself.
If we're brave then we'll develop policy and support systems that guarantee our long term food security, built on a bedrock of environmental, economic, and ethical sustainability.
If we're cowed by the scale of the challenge, then we run the risk of replacing the democratic frustrations of the European Union with a dependence on the tempestuous moods of the global free market.
Today the Prime Minister provided more detail on her vision for leaving the EU. Theresa May confirmed her intention to take Britain out of the Single Market and to manage immigration solely in the interests of the UK.
There are benefits to ending the existing free market in labour. Cutting off a ready supply of low paid immigrant farm workers is no doubt a challenge, but it offers a chance to persuade supermarkets (and through them consumers) to start paying a more realistic price for food. If the cost at the checkout more accurately reflected the costs of production, then this might lead to better pay and conditions for farm workers - and to jobs that more British people are prepared to turn up to do.
Mrs May also made it clear that she wants Britain to become a champion of global free trade. Here be dragons. Challenging barriers to trade and trimming the fat off regulation makes sense - where possible, and where it is in our best interests. But we need to be very clear about the important role that good legislation plays in protecting our long term food security.
Legislative frameworks not only protect workers and the natural world - they play a critical role in creating investor confidence and ensuring long term policy delivery. Recent changes to energy subsidies pulled the rug out from under the UK solar sector, an important income stream for many farmers. The uncertainty around renewables has larger economic implications too. Just this week IKEA announced that it would not be investing the half a billion pounds it had planned to spend on green energy in the UK because the investment environment was too uncertain.
When we leave the EU we should replace European policy with British laws that deliver freedom for farmers to innovate and respond to the honest demands of the market place, with labels that allow direct conversations between consumers and producers, and with financial incentives that reflect the innate value of good animal welfare, landscape management, and improved biodiversity.
The current race to the bottom, in terms of ever greater levels of production for ever less money, is quite simply heading for a crash. There are signs of strain across the industry, but particularly in the plight of the dairy sector, which is competing in a volatile global market place. The future for British farmers must be in developing quality products for defined and discerning markets both at home and abroad.
Post-Brexit policy should set a solid trajectory for British farming to become truly sustainable. Within a decade consumers should be paying for food directly at the checkout, while their tax pounds are used to reward public goods that the market is much less able to recognise, such as flood prevention and soil improvement.
And then there's climate change. The government's focus on global trade, must not be at the expense of domestic stability and growth in the number of small and medium-size farm businesses. It is these smaller, more flexible businesses that will help protect us from the health and security impacts of a warmer world. The most recent Intergovernmental Panel on Climate Change conclusions showed that +2C by 2046 is nearly inevitable, and that +4C is possible. The UK climate expert, Professor Kevin Anderson, has said that a +4C future is incompatible with an organised global community, and is likely to be beyond ‘adaptation’.
Farms have an extremely important role to play in reducing greenhouse gas pollution and improving the land's capacity to sequester carbon. But some warming is inevitable, and if Prof. Anderson is right about the rate of change then we may find that by having too many eggs in the global trade basket our food economy and security is at greater risk. Climate change is a threat multiplier - it makes economic instability, conflict, disease migration, and disrupted transport routes more likely. A heavy dependence on trade with the rest of the world increases these risks still further.
At the same time, our own harvests will become more vulnerable to increasingly frequent extreme weather events, such as floods and droughts. To mitigate and reduce these impacts, so that our own food security is strengthened, we must redesign our farmed landscape so that our soil quality and biodiversity is better recruited for our own community protection.
Leaving the EU means that Britain has a chance to choose its own destiny - but we must make our plans based on the likely challenges of a world twenty years from now.
A rush to embrace the global free market, in the belief that the grass on the other side of the planet is greener, runs the risk of transferring our decision-making ability from a frying pan and into a fire.