The WSJ discusses Energy Secretary Steven Chu’s warning that, in the future under a domestic cap and trade program, the US may levy tariffs on foreign goods to protect American companies from foreign competition not subject to carbon pricing. Is this “climate protection” or “economic protectionism” or both? One point seems clear: regardless of the reasoning a trade war means higher prices for the American consumer, a point sure to be front and center in the cap and trade debate. Here is an excerpt:

Energy Secretary Steven Chu on Tuesday advocated adjusting trade duties as a “weapon” to protect U.S. manufacturing, just a day after one of China’s top climate envoys warned of a trade war if developed countries impose tariffs on carbon-intensive imports.

Mr. Chu, speaking before a House science panel, said establishing a carbon tariff would help “level the playing field” if other countries haven’t imposed greenhouse-gas-reduction mandates similar to the one President Barack Obama plans to implement over the next couple of years. It is the first time the Obama administration has made public its view on the issue.

“If other countries don’t impose a cost on carbon, then we will be at a disadvantage…[and] we would look at considering perhaps duties that would offset that cost,” Mr. Chu said.

Li Gao, a senior Chinese negotiator from the National Development and Reform Commission, told Dow Jones Newswires Monday that a carbon tariff would be a “disaster,” would prompt a trade war and wouldn’t be legal under World Trade Organization agreements

“It does not abide by the rule of [the] WTO and, secondly, it’s not fair,” Mr. Gao said, adding that his delegation would relate China’s concerns to U.S. officials.

Mr. Chu’s comments came amid other signs of concern among U.S. trading partners about protectionist rhetoric and legislation from Washington.