This story has been updated.

On Tuesday, in yet another move — like her opposition to Arctic drilling — that rallied the environmental base, Hillary Rodham Clinton announced her opposition to the Keystone XL pipeline. Speaking in Des Moines, the leading Democratic presidential candidate said Keystone XL had become “a distraction from the important work we have to do to combat climate change” and “interferes with our ability to move forward.”

“Therefore, I oppose it,” Clinton said.

The announcement naturally did not go without criticism — a case in point:

But opposing Keystone XL is not an energy policy, and Clinton went farther Wednesday by outlining what she believes needs to be done to address the United States’ aging and ailing energy infrastructure — including pipelines, transmission systems, and ports that receive and ship out large volumes of fossil fuels. The candidate’s views were announced in a post at Medium and, more extensively, on her campaign Web site.

The flaws and vulnerabilities of the U.S. energy infrastructure were recently highlighted in the Obama administration’s first Quadrennial Energy Review, which found that an array of new challenges are emerging because of climate change, the increasing penetration of clean energy into the grid, and risks related to terrorism and cyber-attacks. The simple aging of the grid doesn’t help, either. There has been a “lack of timely investment in refurbishing, replacing, and modernizing components of [energy] infrastructure that are simply old or obsolete,” noted the Quadrennial Energy Review.

The vast document thus underscored that while the subject of U.S. energy infrastructure may seem wonky and un-glamorous, it is nonetheless a pressing problem.

Addressing it, Clinton wrote at Medium, “is bigger than Keystone XL or any other single project.” So Clinton said that she would seek to address a slew of energy infrastructure problems, many of which were also identified in the Quadrennial Energy Review: too many accidents through the transport of oil by rail; an aging natural gas pipeline infrastructure; a grid that faces reliability concerns and the risk of cyber-attacks.

To that end, Clinton proposes not only a major partnership with Mexico and Canada to in effect green the vast energy trade and transportation system that connects the three countries, but also the forging of an Infrastructure Bank to invest in ailing grid and pipeline networks. “The United States trades as much energy with Canada and Mexico each year as with all other countries combined, through a deeply integrated pipeline network, rail system, and electrical grid,” Clinton wrote at Medium.

The candidate also promised tighter regulations of pipeline siting and oil-by-rail transport. “I will strengthen national pipeline safety regulations and partner with pipeline operators, local regulators, and technology providers in repairing and replacing thousands of miles of the country’s oldest pipes,” Clinton wrote.

At least one environmental organization quickly hailed Clinton’s plans Wednesday. “From updating our energy grid for renewable capacity to getting dangerous, unsafe crude oil trains off the rails, the initiatives she lays out will go a long way toward keeping our air and water clean and our families safe,” said Sierra Club executive director Michael Brune in a statement.

But some reactions were a bit more critical. “Clinton’s emphasis on modernizing energy infrastructure is welcome and long overdue, as investment has languished in Congress which hasn’t kept infrastructure investment and gasoline taxes equal with inflation for a quarter century,” said Paul Bledsoe, a former Clinton White House climate staff member, in reacting to the plan by email. “But the most dynamic energy innovation will come about as part of tax reform eliminating fossil fuel subsidies and providing clear incentives for deployment of low emissions energy resources, including efforts on carbon capture. That level of detail will be needed to advance these issues seriously.”

Notably, while her opposition to Arctic drilling certainly takes a step in this direction, Clinton did not directly address the production of fossil fuels on U.S. public lands in the new announcements. This is a growing concern for many “supply side” environmental activists, who have targeted fossil fuel infrastructure projects that they believe push the world towards busting its remaining carbon budget and have recently called for a cessation of all new federal fossil fuel leases, their strongest stance yet.

Clinton’s remarks about pairing with Canada and Mexico to weigh energy infrastructure projects based on their climate change implications, however, could imply possible steps down this road. If Keystone XL wouldn’t pass her test, it stands to reason that other potential projects might not, as well. And Clinton’s focus on problems with pipelines and oil trains also plays to recurrent concerns expressed by green activists about the dangers of drilling for and transporting fossil fuels.

Combined with her views on Arctic drilling, then, it all suggests that a Clinton presidency might tack more to the environmental left than Obama’s has.

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