美国开征碳税正当其时

The case for carbon taxes has long been compelling. With the recent steep fall in oil prices and associated declines in other energy prices it is overwhelming. There is room for debate about the size of the tax and about how the proceeds should be deployed. But there should be no doubt that starting from the current zero tax rate on carbon, increased taxation would be desirable.

碳税问题长期以来一直备受关注。随着近期油价暴跌以及其他能源价格的相应下挫，征收碳税已是势在必行。我们有讨论碳税的规模以及税收如何运用的空间。但毫无疑问的是，以当前碳排放零税率为起点而增加的税收将是可行的。

The core of the case for taxation is the recognition that those who use carbon-based fuels or products do not bear all the costs of their actions. Carbon emissions exacerbate the global climate change problem. In many cases they contribute to local pollution problems which immediately harm human health. Removing fossil fuels from the ground involves both accident risks and environmental challenges. And even with the substantial increases in US oil production we remain a net importer, so increases in consumption raise our dependence on Middle East producers.

碳税问题的核心是承认那些使用碳基燃料或产品的消费者没有承担他们行为的所有费用。碳排放加剧了全球气候变化问题。在许多情况下，它们会造成当地的污染问题，这些问题又直接危害人类健康。将化石燃料从地下开采出来既包含事故隐患，也带来环境挑战。尽管美国石油产量大幅增加，我们仍是石油净进口国，所以石油消耗增加提升了我们对中东石油生产国的依赖程度。

When we drive our cars, heat our homes or use fossil fuels in more indirect ways, all of us create these costs without paying for them. It follows that we overuse these fuels. This is not some kind of government planning argument — it is the logic of the market: that which is not paid for is overused. Even if the government had no need or use for revenue, it could make the economy function better by levying carbon taxes and rebating the revenues to society.

当我们驾驶汽车，烘暖房间或通过更间接的方式使用化石燃料时，我们大家产生了这些费用，却没有付费。由此可见，我们过度使用了这些燃料。这不是某种政府策划的结论，而是市场逻辑：不用付费的资源必然被滥用。即使政府不需要或者用不着这部分收入，它也可以通过征收碳税、再返还社会的方式使经济运转得更良好。

While the recent decline in energy prices is a good thing in that it has on balance raised the incomes of Americans, it does exacerbate the problem of energy overuse. The benefit of imposing carbon taxes is therefore enhanced.

虽然，总的来说，近期能源价格下跌对提高美国民众收入是一件好事，但这的确加剧了能源过度使用的问题。征收碳税的裨益因此也大大增加。

On the other side of the ledger, there has always been the concern that raising carbon taxes would place an unfair burden on some middle- and low-income consumers. Those who drive long distances to work, say, or who have homes that are expensive to heat would be disproportionately burdened. Now these groups have received a windfall from the drop in energy prices so it would be possible to impose substantial carbon taxes without them being burdened relative to where prices stood six months ago. As an example, the price of petrol has fallen by over $1 per gallon. A $25 a tonne tax on carbon that would raise over $1tn during the next decade would lift petrol prices by only about 25 cents.

另一方面，一直以来人们就担心，提高碳税会对一些中低收入消费者造成不公平的负担。比如，那些远途开车的上班族、或者房屋供暖费用昂贵的人将承受过重的负担。现在，这些群体已从能源价格下跌中获得不少好处，所以征收相当程度的碳税而又不增加他们的负担（相对于6个月前的油价水平）是可行的。例如，汽油价格已下跌逾1美元/加仑。如果每吨二氧化碳排放征收25美元的碳税，未来10年的税收将超过1万亿美元，而汽油价格每加仑仅会提高约25美分。

Some worry that taxing fossil fuels will hurt the competitiveness of US industry and encourage offshoring. In fact a well designed tax would be levied on the carbon content of all imports coming from countries that did not impose their own carbon levies. The US should insist that its tax is compatible with World Trade Organisation rules. It would have the virtue of encouraging countries who wished to avoid the US tax to impose carbon taxes of their own, thereby further supporting efforts to reduce global climate change.

一些人担心对化石燃料征税将损害美国的工业竞争力，并鼓励产业外移。实际上，通过精心设计，美国将对所有进口商品的碳含量进行征税，如果这些产品的出口国没有对它们课征碳税的话。美国应坚持其所征之税不违背世界贸易组织(WTO)的规则。这样美国就可以有资格鼓励那些希望免受美国课税的国家征收本国的碳税，从而进一步支持减缓全球气候变化的努力。

A US carbon tax would contribute to efforts to combat climate change in other ways. It would be a hugely important symbolic step ahead of the global climate summit in Paris late this year. It would shift the debate towards harmonised measures to raise the price of carbon use and away from the complex cap-and-trade type systems that in the EU and elsewhere have proven more difficult to operate than expected.

美国征收碳税在其他方面也将有助于应对气候变化的努力。今年底巴黎召开全球气候变化峰会之前，它将是非常重要的象征性一步。它将把讨论引向通过采取协调一致措施提高碳使用的价格，并使讨论避开复杂的“限额与交易”(cap-and-trade)型机制，欧盟及其他地方的经验已证明这类机制比预期的更难操作。

What size levy is appropriate? Here there is more danger of doing too little than too much. Once the principle of taxation is accepted its level can be adjusted. A tax of $25 a tonne would raise well over 1 per cent of US gross domestic product, or $150bn, each year and seems a reasonable starting point.

碳税多大规模合适呢？在这一点上，征得太少比太多反而危险更大。一旦征税原则被接受，其标准是可以调整的。如果每吨二氧化碳排放征税25美元，每年将带来大大超过美国国内生产总值(GDP) 1%的收入（1500亿美元），这看起来是一个合理的出发点。

How should the proceeds be used? Here too it seems more important to reach consensus on the principle of taxation. My preference would be for the proceeds to be split between investments in infrastructure and pro-work tax credits. An additional $50bn a year in infrastructure spending would be a significant contribution to closing America’s investment gap in that area. The same sum devoted to pro-work tax credits could finance a huge increase in the earned income tax credit, a meaningful reduction in the payroll tax or some combination of the two.

这些收入该如何使用呢？同样地，在税收原则上达成共识看起来更加重要。我倾向于将这些收入平分，用于基础设施投资和促进就业的税收减免。每年增加500亿美元的基础设施支出将为美国弥补此领域的投资不足做出巨大贡献。将同样数额的碳税收入用于促进就业的税收减免，可以大幅增加所得税减免、显著降低工资税或两者相结合。

Progressives who are concerned about climate change should rally to a carbon tax as the most important step for mobilising against it. Conservatives who believe in the power of markets should favour carbon taxes on market principles. And Americans who want to see their country lead on the energy and climate issues that are crucial to the world this century should want to be in the vanguard on carbon taxes. Now is the time.

关注气候变化的进步人士应该共同支持把征收碳税作为动员大家应对气候变化的最重要一步。相信市场力量的保守派人士也应该赞同符合市场规则的碳税。希望看到自己国家在对当今世界至关重要的能源和气候问题上发挥领导作用的美国人，应该希望在碳税问题上发挥先锋作用。现在正当其时。