More than 100 world leaders arrived in Glasgow this week to discuss a problem almost every government now officially agrees exists.
That should make cooperation relatively easy.
It doesn’t.
COP26 has produced an extraordinary collection of promises already. More than 100 countries have backed a pledge to reduce global methane emissions by 30% from 2020 levels by the end of this decade. More than 100 leaders have also promised to halt and reverse forest loss and land degradation by 2030. Governments and financial institutions are making new commitments involving coal, clean energy, climate finance and investment.
India made one of the summit’s most important announcements. Prime Minister Narendra Modi committed the country to reaching net-zero emissions by 2070. He also announced nearer-term objectives for 2030, including increasing non-fossil electricity capacity and reducing the carbon intensity of India’s economy.
The immediate criticism is obvious: 2070 sounds extremely late. The United States and European Union are targeting net zero by 2050. China says it intends to reach carbon neutrality before 2060.
But comparing those dates without comparing the countries behind them misses most of the politics.
India’s GDP per person remains far below that of the United States or Western Europe. Hundreds of millions of Indians are still moving towards levels of consumption that citizens in richer countries have taken for granted for decades. India needs more electricity, transport, housing, manufacturing and infrastructure. All of those things require energy.
The political question is therefore not simply how quickly India can stop emitting carbon.
It is whether India can become substantially richer while simultaneously changing the energy system through which countries historically became rich.
That is a much harder problem.
Climate change is unusual because the atmosphere does not care where a tonne of carbon dioxide was emitted. Carbon released in Mumbai affects the same climate system as carbon released in Texas or Shanghai.
National politics works differently.
Governments answer principally to their own citizens. An Indian government is judged by Indian voters. An American president is judged by Americans. A Chinese government is principally concerned with political stability and economic performance inside China.
This creates the central climate problem.
The benefits of reducing emissions are global, while many of the costs are local.
If India closes a coal plant, India bears much of the immediate economic adjustment. The climate benefit is distributed across the planet.
If every country reasons that way and waits for everybody else to act first, emissions continue rising.
Economists call this a collective-action problem, but the phrase almost makes it sound more technical than it is. Imagine ten people sharing a room that is becoming dangerously hot. Everyone benefits if the air conditioner is repaired, but repairing it costs money. Each person would prefer the other nine to pay.
If everyone behaves rationally from an individual perspective, nobody pays.
Everyone becomes worse off.
Climate diplomacy is essentially that problem involving almost 200 countries, trillions of dollars and several generations.
Except the countries did not contribute equally to creating the problem.
That is where the argument becomes much more difficult.
Industrialisation began in Britain and spread across Europe and North America long before countries such as India produced substantial emissions. Wealthy countries built factories, railways, electricity systems, cities and enormous consumer economies using fossil fuels.
The carbon dioxide released during much of that development remains relevant to today’s warming.
Developing countries therefore make a powerful argument: rich countries used cheap fossil energy to become rich and are now asking poorer countries to restrict the same pathway.
From India’s perspective, climate justice means recognising historical responsibility as well as current emissions.
The United States may currently be reducing emissions from extremely high levels after spending more than a century building its economy through carbon-intensive growth. India is being asked to reduce the carbon intensity of development before reaching anything close to American living standards.
Treating those situations as identical would not be fair.
But historical responsibility creates another problem.
The atmosphere responds to future emissions regardless of whether those emissions are morally fair.
India can correctly argue that its historical contribution to climate change is much smaller than America’s. If India, China and other developing economies nevertheless produce enormous future emissions, global temperatures will still rise.
Climate physics does not contain an exemption for historical injustice.
That means two propositions can be simultaneously true: wealthy countries bear greater responsibility for creating the problem, and developing countries still have to participate in solving it.
The political challenge is determining how the costs should be divided.
This is why climate finance matters so much.
Wealthy countries previously promised to mobilise $100 billion per year in climate finance for developing countries by 2020. That target has not been fully met.
One hundred billion dollars sounds enormous until it is compared with the scale of transforming the global energy system. But the broken promise matters beyond the amount itself.
It affects trust.
Imagine wealthy countries telling India, South Africa or Indonesia that they need to accelerate the retirement of coal plants because climate change is an emergency. Developing countries can reasonably respond: you promised financial assistance for this transition and did not deliver it on time.
International cooperation depends on reciprocity.
If one group repeatedly fails to fulfil its commitments, the other group has less reason to accept costly new ones.
This is where the language of climate leadership sometimes becomes irritatingly easy.
A European government can announce an ambitious emissions target and receive international praise. But if carbon-intensive manufacturing has simply moved elsewhere, part of the apparent achievement reflects geography rather than genuine decarbonisation.
A country can reduce domestic emissions while importing steel, electronics, clothing and other products whose emissions occur in another country.
The atmosphere sees the carbon.
National emissions accounts see the border.
That doesn’t make national targets useless. It means consumption matters alongside production.
Otherwise rich countries risk congratulating themselves for becoming cleaner while continuing to consume products manufactured through emissions occurring somewhere else.
There is also an enormous difference between a target and a policy.
Net zero by 2050.
Net zero by 2060.
Net zero by 2070.
These dates dominate headlines because they are easy to communicate.
But a promise about 2070 is politically cheap in 2021.
Narendra Modi will not be prime minister in 2070. Joe Biden will not be president in 2050. Almost every leader making long-term commitments at COP26 will be long gone when the deadline arrives.
That creates a political accountability problem.
Governments receive some benefit today from announcing ambitious future targets while much of the cost can be transferred to future governments.
The further away the deadline, the easier this becomes.
That is why India’s 2030 commitments may ultimately tell us more than the 2070 headline.
Intermediate targets constrain governments sooner. They allow voters, investors and other countries to ask whether actual emissions, renewable capacity and energy investment are moving towards the promised trajectory.
A credible climate policy therefore needs milestones.
Otherwise net zero risks becoming a political promise made by people who know they will never personally have to explain why it was missed.
The same problem applies to this week’s methane agreement and forest pledge.
More than 100 countries promising to stop deforestation sounds transformative. Similar commitments have been made before.
The question is what changes tomorrow morning.
Will governments stop subsidising activities that destroy forests? Will enforcement improve? Will indigenous communities receive stronger land rights? Will businesses face rules preventing commodities linked to illegal deforestation from entering supply chains?
A declaration is an intention.
Policy changes incentives.
Only the second reliably changes behaviour.
Methane is particularly interesting because reducing it could produce relatively rapid climate benefits. Methane remains in the atmosphere for a much shorter period than carbon dioxide but is extremely powerful at trapping heat. Cutting emissions from oil and gas systems, agriculture and waste could therefore slow warming more quickly than carbon reductions alone.
Yet even here, countries disagree over costs and capabilities. India has not joined the Global Methane Pledge announced this week. Agriculture is politically sensitive, and methane emissions in countries with large livestock sectors cannot be treated exactly like leaks from an American oil field.
Again, a global target meets domestic politics.
Every climate solution eventually does.
Coal demonstrates the problem most clearly for India.
Coal is highly carbon intensive.
It is also deeply embedded in India’s electricity system and economy. Millions of livelihoods are connected directly or indirectly to coal production, transport and coal-dependent industries.
Saying “phase out coal” therefore sounds much easier at a climate conference than it does in a district where the mine provides jobs, government revenue and electricity.
This does not mean coal should remain forever.
It means transition has distributional consequences.
Someone loses.
Workers need alternative employment. Regions need replacement investment. Electricity systems need reliable generation when renewable output fluctuates. Consumers need power that remains affordable.
A climate policy that ignores these costs may be environmentally ambitious and politically unsustainable.
And politically unsustainable climate policy eventually becomes environmentally ineffective because governments reverse it.
That may be one of the most important lessons for climate politics: fairness is not separate from effectiveness.
A transition perceived as unfair creates opposition.
The French fuel-tax protests several years ago demonstrated how quickly climate policy can become politically explosive when households believe they are being asked to absorb costs disproportionately.
Governments therefore need to design policies that change incentives while compensating people who bear concentrated losses.
Carbon pricing is a good example.
Economically, putting a price on carbon makes sense because emitting greenhouse gases imposes costs that markets otherwise do not fully include. If carbon becomes expensive, consumers and firms have incentives to choose cleaner alternatives.
Politically, however, a carbon price can look like higher petrol, electricity or heating costs.
The economic logic may be excellent.
The voter sees the bill.
Policy design therefore matters. Revenue can be returned to households, invested in clean infrastructure or used to reduce other taxes. Without those mechanisms, economically efficient policy can become politically impossible.
This is where I think economists and politicians sometimes talk past each other.
Economists ask: What policy reduces emissions at the lowest overall cost?
Politicians have to ask another question: Who experiences that cost, when do they experience it, and do they know who imposed it?
Those are not objections to economics.
They are part of implementing it.
China creates another enormous complication.
China is currently the world’s largest annual emitter of carbon dioxide, but it is also the world’s largest manufacturer and installer of many clean-energy technologies.
That makes simple categories difficult again.
China can simultaneously be central to the climate problem and central to its technological solution.
The United States and China are geopolitical competitors. They disagree over Taiwan, trade, technology, human rights and military power.
They also share one atmosphere.
Climate change therefore creates an unusual area in which two strategic competitors have strong reasons to cooperate even while competing elsewhere.
This resembles the nuclear relationship between America and Russia I wrote about after Biden met Putin in June. Countries do not need to trust one another completely to cooperate on a problem where failure harms both.
Climate diplomacy may ultimately depend on that kind of compartmentalisation.
Washington and Beijing can compete over semiconductors while negotiating emissions.
India and China can confront one another along their border while both investing in renewable energy.
International politics does not require one relationship to have one character.
The question is whether governments can prevent geopolitical rivalry from contaminating every issue simultaneously.
There is also an intergenerational problem that makes climate change different from almost every political issue.
The people making decisions today will experience only part of the consequences.
Young people will experience much more.
People not yet born will experience consequences without having any political voice in the decisions producing them.
Democracy normally works because voters can punish politicians for bad outcomes.
Future citizens cannot vote in today’s election.
That means climate policy has a representation problem.
Governments have incentives to prioritise immediate costs and benefits because current voters determine whether they remain in office. Spending money today to avoid damage in 2070 asks politicians to impose visible costs on people who vote now for benefits partly received by people who cannot.
Institutions therefore need mechanisms that extend political time horizons.
Independent climate commissions, legally binding carbon budgets, transparent intermediate targets and long-term investment frameworks may matter partly because they make it harder for every new government to restart climate policy from zero.
Again, institutions attempt to solve an incentive problem.
COP26 will ultimately be judged by whether it changes those incentives.
The speeches are useful. Targets matter because they coordinate expectations. Investors deciding whether to finance a coal plant or solar project care about where governments say policy is going. Businesses designing vehicles for the 2030s care about future emissions standards.
Promises can therefore influence behaviour before becoming law.
But credibility determines how strongly.
If governments repeatedly announce targets and miss them, businesses discount the next promise.
If rich countries promise climate finance and fail to provide it, developing countries discount the next offer.
If every summit is described as the world’s “last chance”, eventually the phrase loses meaning.
Climate politics therefore requires something much less dramatic than another declaration of emergency.
It requires credible repetition.
Set targets.
Implement policy.
Measure progress.
Correct failure.
Transfer money that was promised.
Return next year and do it again.
That is less inspiring than a photograph of 100 world leaders standing together in Glasgow.
It is probably how decarbonisation actually happens.
India’s 2070 commitment will inevitably be criticised for arriving twenty years after the targets of the United States and European Union.
Perhaps it should be more ambitious.
But the fairness of India’s target cannot be evaluated by comparing dates alone. India has contributed much less historically per person, remains far poorer and still needs enormous development.
At the same time, India cannot use historical responsibility as a permanent argument for unlimited future emissions. India will be one of the countries most exposed to climate change itself, through heat, water stress, changing monsoons and other risks.
Its interest in decarbonisation is therefore not simply something imposed by Western governments.
The real question is how quickly India can make clean development cheaper than carbon-intensive development.
If solar power, storage, electric transport and green industrial technologies become economically superior, the conflict between development and climate policy becomes much smaller.
That may ultimately matter more than moral arguments about which country deserves to emit what.
Technology can change the political bargaining problem by changing the cost of cooperation.
If clean energy becomes cheaper than fossil energy, governments no longer have to choose as sharply between economic growth and emissions reduction.
Climate policy therefore needs investment and innovation alongside restrictions.
Perhaps that is where the most realistic optimism lies.
Not in expecting almost 200 governments suddenly to prioritise humanity over national interest.
Governments will continue pursuing national interest.
The task is to construct policies and technologies that make national interest increasingly compatible with global decarbonisation.
That is a less romantic theory of international cooperation.
It may be more durable.
COP26 is filled with speeches about a common future, shared responsibility and saving the planet.
All of that is true.
But political systems do not usually succeed because everyone becomes selfless.
They succeed when institutions make cooperation rational even for actors who remain self-interested.
Climate change is perhaps the largest attempt humanity has ever made to construct such a system.
Everyone benefits if it succeeds.
Everyone has incentives to let somebody else bear more of the cost.
Rich countries want developing countries to decarbonise faster. Developing countries want rich countries to pay more. Fossil-fuel producers want slower transition. Climate-vulnerable states want much faster action. Current voters dislike higher costs. Future generations cannot vote.
That is why agreement that climate change is real was never going to be enough.
The scientific problem is extraordinarily difficult.
The political problem may be harder.
We know broadly what has to happen: global greenhouse-gas emissions have to fall dramatically.
What Glasgow has to determine is something science cannot answer:
who pays, how much, and when?
Until governments can answer that question in a way enough countries consider fair, the world can agree completely about the problem and still fail to solve it.
