President Donald Trump signed an executive order yesterday at the headquarters of the Environmental Protection Agency that purported to roll back much of former President Obama’s policies on climate change by ordering a reevaluation of Obama’s Clean Power Plan and lifting the ban on federal land leasing for coal production.

The president promised coal miners that they would be going back to work. He also reiterated the policy, articulated in an earlier executive order, that pipelines built in the United States would be made of steel fabricated domestically.

“We will put our miners back to work,” Trump said. “We’re going to have clean coal — really clean coal.”

Trump went on to connect jobs for miners to jobs for steelworkers through his approval of the permits to build the Keystone XL pipeline and complete the Dakota Access pipeline.

“We want to make our goods here instead of shipping them in from other countries,” said Trump. “We will transport American energy through American pipelines, made with American steel.  Made with American steel.”

Trump’s new coal policy may help the coal industry, but not to the extent that he or the coalminers may think. The coal industry has declined primarily because of met conditions: power plants have moved to cheap natural. Over 80 percent of the coal mined in this country historically has been used for power generation.

Coal has also been losing out in recent years to clean energy alternatives. Coal currently supports 66,000 jobs in the United States. Clean energy has three million. Also, there’s no such thing as clean coal. Technology exists that help coal burn cleaner but most power companies have found it’s not cost effective to implement.

As far as the pipelines, it’s been widely reported that Keystone won’t be using US-made steel. Besides, despite what Trump says, it’s not his formal policy to require the use of American steel in domestic pipelines. A presidential memorandum signed on January 24 instructed the Secretary of Commerce to develop a plan within 180 days for all new pipelines within the United States to be constructed with US materials and equipment “to the maximum extent possible and to the extent permitted by law.” That leaves the Commerce Department and the administration a lot of wiggle room.

“To the extent permitted by law” could be a major stumbling block to the execution of Trump’s preferences as a US-only policy could well run afoul of the rules of the World Trade Organization (WTO), which Trump detests but is still bound by, and the WTO’s Government Procurement Agreement (GPA), to which the US is a signatory. WTO rules enshrine the principle of non-discrimination between domestic producers and foreign suppliers.

Simply put, the US president doesn’t have the authority to dictate to pipeline builders where to source their steel.