Posted in the Wall Street Journal Opinion Journal

By RALPH NADER and TOBY HEAPS

If President Barack Obama wants to stop the descent toward dangerous global climate change, and avoid the trade anarchy that current approaches to this problem will invite, he should take Al Gore’s proposal for a carbon tax and make it global. A tax on CO2 emissions — not a cap-and-trade system — offers the best prospect of meaningfully engaging China and the U.S., while avoiding the prospect of unhinged environmental protectionism.

China emphatically opposes a hard emissions cap on its economy. Yet China must be part of any climate deal or within 25 years, notes Fatih Birol, chief economist at the International Energy Agency, its emissions of CO2 could amount to twice the combined emissions of the world’s richest nations, including the United States, Japan and members of the European Union.

According to the world authority on the subject, the Intergovernmental Panel on Climate Change (IPCC), it will cost $1.375 trillion per year to beat back climate change and keep global temperature increases to less than two degrees Celsius (3.6 degrees Fahrenheit).

Cap-and-traders assume, without much justification, that one country can put a price on carbon emissions while another doesn’t without affecting trade or investment decisions. This is a bad assumption, given false comfort by the Montreal Protocol treaty, which took this approach to successfully rein in ozone-depleting gases. Chlorofluorocarbons are not pervasive like greenhouse gases (GHGs); nor was the economy of 1987 hyperglobalized like ours today.

Good intentions to limit big polluters in some countries but not others will turn any meaningful cap into Swiss cheese. It can be avoided by relocating existing and new production of various kinds of CO2-emitting industries to jurisdictions with no or virtually no limits. This is known as carbon leakage, and it leads to trade anarchy.

How? The most advanced piece of climate legislation at the moment, the Lieberman-Warner Climate Security Act, contains provisions for retaliatory action to be taken against imports from carbon free-riding nations. Married with the current economic malaise, the temptation to slide into a righteous but runaway environmental protectionism — which Washington’s K Street lobbyists would be only too happy to grease — would almost certainly lead to a collapse of the multilateral trading system. This scenario was presented to the world’s trade ministers last December at the United Nations climate talks in Bali by David Runnalls of the International Institute for Sustainable Development.

True, trade anarchy might reduce emissions via a massive global depression. But there would be a lot of collateral damage. Because of the sheer scale of the challenge and the state of the hyperglobalized economy, we will need the same price on carbon everywhere, or it won’t work anywhere.

President Obama can define his legacy in the first 100 days by laying the groundwork for a global tax on carbon dioxide emissions that is effective, efficient, equitable and enforceable. An effective, harmonized tax on C02 emissions must stabilize the growth of atmospheric concentrations of GHGs by no later than 2020. The tax must also be adjusted annually, by a global body, according to this objective.

The IPCC has crunched the numbers and says this means a tax of about $50 levied on every metric ton of GHGs, or carbon dioxide equivalent (CO2e to use their terminology). In the short-term, consumers would feel the pinch. But the tax would pave the way for cheaper, cleaner energy and ways of getting around.

The most efficient way to apply a carbon tax is at a relatively small number of major carbon bottlenecks, which cover the lion’s share of GHGs. The key points where flows of carbon are the most concentrated include: trunk pipelines for gas, refineries for oil, railroad heads for coal, liquid natural gas (LNG) terminals, cement, steel, aluminum and GHG-intensive chemical plants.

Collecting and spending the bulk of revenues from a carbon tax must remain the sovereign right of participating nations. For instance, nations could decide to make the tax revenue-neutral by reducing taxes on income or helping finance industrial retooling for a green economy.

However, we in the rich world must recognize our culpability for creating three-quarters of this global warming mess, as well as our greater capacity to finance industrial retooling. Thus, there could be a carrot for developing-world nations which commit to applying the phased-in carbon tax: Access to a portion of the carbon tax levies from rich countries to help preserve forests and to prepare for climate change through flood walls, improved irrigation, drought resistant crops, desalination facilities, and the like. This is no small change: 10% of $50/metric ton CO2e carbon tax levied in all rich countries would be $100 billion per year. The stick for carbon free-riding countries would come in the form of incrementally severe penalties, leading up to countervailing duties on carbon-intensive imports.

A global carbon tax levied on a relatively small number of large sources can be monitored by satellite and checked against the annual surveillance of fiscal and economic polices already carried out by IMF staff. Thus, the accounting involved is much more precise and much less subject to the vagaries of corruption and conflict over which industries and companies get their free handouts of carbon credits — carbon pork — than in a cap-and-trade system.

There are three reasons why countries, such as China and India, that have traditionally resisted any notion of a common responsibility to make current polluters pay would do well to enlist in this effort.

First, while there is no limit on the downside for missing a hard cap, with a carbon tax you just pay as you go. If a fast-growing country like China accepted an emissions cap and then overshot it, they would have to purchase carbon credits on the international market. If they missed their target by a lot, carbon credits would be scarce, and purchasing them would suck dry their foreign exchange reserves in one slurp. That’s why a carbon tax is much easier to swallow and, anyway, through the power of the price signal, it would produce the same desired result as a hard cap.

Second, administering billions of dollars of carbon credits in a cap-and-trade system in an already chaotic regulatory environment would invite a civil war between interest groups seeking billions in carbon credit handouts and the regulator holding the kitty. By contrast, a uniform tax on CO2 emissions levied at a small number of large sites would be relatively clear-cut. During the Montreal Protocol talks in the 1980s, India smartly balked at a suggestion to phase out CFCs in certain products and not in others because of the chaos that would result from the ambiguity.

Third, key people in China read our newspapers. They see the ominous clouds of protectionism under the guise of environmentalism in bills like Lieberman-Warner and they don’t want to be harmed; neither should we, given the trillions of dollars of Treasury bills they hold. Showing compliance with a harmonized carbon tax at a small number of large bottleneck points would be child’s play compared to the chaos of cap-and-trade.

If President Obama hits the ground running fast in the direction of a global carbon tax, he can usher in a new dawn that might finally make peace between man and climate.

Mr. Nader is a consumer advocate and three-time presidential candidate. Toby Heaps is the coordinator of Option 13, a campaign to help broker a successor to the Kyoto Protocol that includes all major nations.