As if to ward off criticism for not including the controversial project, Obama said, "Our energy strategy . . . has to be about more than just building one pipeline."
He also said the pipeline, which would carry crude from Canada's oil sands to refineries in the Gulf of Mexico, would be approved "only if it doesn't exacerbate the impact of carbon pollution."
This is more negative than Obama has ever been about Keystone. In the past, the only signals he gave on its prospects for approval have been positive ones. After Transcanada's application to build the north-south conduit was hung up over objections from the state of Nebraska, the president encouraged the company to go ahead go ahead and build the southern part of it -- from Oklahoma to the Gulf Coast -- and submit a new application for the section from Canada to Oklahoma.
And he certainly didn't criticize Keystone during the 2012 campaign.
Does today's statement suggest that Obama is changing his mind?
It's true that the State Department's most recent environmental impact statement on the project, released in March, says the pipeline wouldn't lead to significantly more carbon pollution. So Obama could be just laying the verbal groundwork for approving the project later this year.
But as U.S. oil production increases beyond what anyone predicted even a few years ago, Keystone becomes somewhat less vital to the U.S. economy and its energy security. Maybe, after so much delay and so much protest, the pipeline's prospects are growing dimmer.
It's always seemed that, in opposing Keystone so stridently, climate activists chose the wrong target. They would have been smarter to spend their energy fighting coal-fired power. Based on what Obama said today, it seems they might end up winning both battles.
(Mary Duenwald is a member of the Bloomberg View editorial board.)