his week the French national assembly voted to ban domestic flights on routes that could be travelled via train in under two and a half hours. The new rule, which is the result of a French citizens’ climate convention established by Emmanuel Macron in response to the gilets jaunes (yellow vests) movement, will capture 12% of French domestic flights. Though it’s more moderate than the convention’s initial proposal, which sought to ban all domestic flights on routes with rail alternatives of less than four hours, this is the first time any major economy has prohibited domestic air travel for environmental reasons. It’s also far more drastic than anything the UK has done to curb flight emissions. The huge blow the pandemic has dealt to the aviation industry could be an opportune moment to rethink the future of flights. Before Covid, air travellers rated around half of all flights as unnecessary. Apart from a few exceptions in particularly remote regions, domestic flights in small countries must be among the least necessary of all. Just over half a million flights were taken every year between London and Manchester before the pandemic, a journey that takes around two hours by train. Because so much of the pollution from any given flight takes place during take-off and landing cycles, the emissions produced per kilometre for each passenger on a domestic route are 70% higher than long haul flights – and six times higher than if the same journey was made by rail. But here in the UK, we’re not exactly seizing the moment. Government measures to address aviation emissions are limited to funding speculative techno-fixes via initiatives such as the “jet zero” council, a partnership that aims to deliver the first zero carbon long haul flight by 2050. Such programmes may be necessary, but they are not sufficient. And the aviation sector has a worryingly poor track record when it comes to delivering on sustainability promises. In 2019, airlines used 50m litres of alternative jet fuel – less than 1% of the International Air Transport Association’s goal for 2020. Indeed, the UK Climate Change Committee (CCC) advises that zero-carbon aviation is “highly unlikely” to be feasible by 2050, and that the development of novel fuels “is highly speculative and should not be relied upon”. Even if we can develop some technological solutions to aviation emissions, the CCC still finds that deliberate policies to limit the demand for flights will be needed to reach climate targets. There are easy ways to do this, including introducing some form of frequent flyer levy, scrapping air miles and banning private jets. But instead of limiting the demand for flights, the Treasury is consulting on a plan that would have the opposite effect: halving tax on domestic flights by cutting air passenger duty. APD is a tax charged on all outbound flights from UK airports, so domestic passengers effectively pay twice for return journeys (as both legs of a domestic trip are classed as outbound flights). The Treasury has suggested cutting APD on domestic flights and raising it on international flights. The aviation lobby deeply resents APD, and have waged a longstanding campaign (of which Grant Shapps, the secretary of state for transport, is a supporter) against the tax. But cutting APD on domestic flights will make them cheaper, boosting demand and driving up domestic emissions as a result. Meanwhile increasing APD on long-haul flights is likely to have little effect on emissions, since demand for these flights is far less influenced by small changes in ticket prices. As air travel is already zero rated for VAT (alongside wheelchairs and baby clothes) and jet fuel is exempt from fuel duty by international treaty, slashing the only tax that is applied to domestic flights seems a confused priority for the government – particularly while it’s gearing up to host the crucial Cop26 global climate summit. Moreover, the Treasury consultation on this scheme features a section dedicated to explaining why it has no intention of introducing a frequent flyer levy either (its rationale is that a levy would be too complex). We shouldn’t overstate the impact of the French domestic flight ban – or the extent to which its politicians are listening to its citizens’ concerns about the climate crisis. After Macron initially promised to present recommendations from France’s citizens’ climate convention to parliament “without filter”, his team then spent months watering down the proposals. Now, only flights between Paris and airports such as Bordeaux, Lyon and Nantes will be affected by the new rule, yet most French domestic flights are between Paris and the south, such as Toulouse, Marseille and Nice. Connecting flights will also be exempt. To round off the cynic’s perspective on this announcement, it is instructive to note that the French government’s €7bn Covid bailout to Air France last spring came with a condition attached: ending flights on routes with rail alternatives of under two and a half hours. At the time, the partly state-owned airline complained that the ban should apply to other airlines too – and now it will. It’s a happy coincidence for Air France bosses, who are unlikely to be losing much sleep over the new conditions for another reason too; pre-pandemic, the company’s domestic network was operating at a €200m annual loss. Nevertheless, the French bill still compares favourably with the efforts of the UK government when it comes to aviation emissions, by virtue of this key distinction: the ban recognises that we can’t tackle climate change without some actual curbs on air travel. Up until now, the idea that there might be hard limits to consumption in a carbon-constrained world has been anathema to politicians everywhere. This ban is an important step towards accepting that curbing consumption is essential for driving down emissions. Finding fair ways to impose these limits in practice will be difficult. But banning unnecessary domestic flights should be the easiest place to start. Leo Murray is co-founder and director of innovation at climate charity Possible