IN AN INTERVIEW that Rolling Stone published Wednesday, President Obama said that he thinks climate change will be a big issue in the coming election and that he will be “very clear” about his “belief that we’re going to have to take further steps to deal with climate change in a serious way.”

That would be a welcome switch. So far, dealing forthrightly with the world’s rising temperatures has been far down the list of priorities in Washington, and the president has shown little willingness to stick his political neck out on the issue. In his first two years, he chose to push through health-care reform and then financial reform instead of energy legislation. Mr. Obama’s attempts to revive the Democrats’ cap-and-trade plan during the 2010 election season quickly led to nothing, as have his more recent but barely discussed proposals to require utilities to generate more power from clean sources.

The president didn’t even see fit to mention the words “climate change” or “global warming” in his 2011 State of the Union address. White House rollouts on energy policy have mostly focused on energy independence or green jobs but not on the global threat of warming.

In fairness, Republicans deserve blame for stifling fair discussion of the issue. And Mr. Obama can cite some achievements: He pushed through landmark fuel-efficiency standards for cars and trucks; he invested in renewable energy sources and energy efficiency through the stimulus. The Environmental Protection Agency has been working on greenhouse gas rules. But those won’t adequately attack the big problem: how Americans produce and consume energy, particularly electricity, on the largest scale. That requires a robust, economy-wide solution, such as a carbon tax or, yes, a simple cap-and-trade program.

In his Rolling Stone interview, the president expressed frustration that “internationally, we have not made as much progress as we need to make.” Surely, though, the inattention from leaders such as Mr. Obama has contributed to the slow progress at home, which is a major reason for the slow progress abroad. As a 2007 Foreign Affairs article explained, strong U.S. action is critical to international efforts to defeat this “epochal, man-made threat to the planet”:

“As the world’s largest producer of greenhouse gases, America has the responsibility to lead. While many of our industrial partners are working hard to reduce their emissions, we are increasing ours at a steady clip. . . . We need a global response to climate change that includes binding and enforceable commitments to reducing emissions, especially for those that pollute the most: the United States, China, India, the European Union, and Russia.”

The writer was Sen. Barack Obama.

Climate change is one of the great challenges of this century, and the country needs a big, realistic debate about policy to address the threat. We encourage Mr. Obama to follow through on his words, giving the issue — and truly serious ways to deal with it — the prominence they deserve in this year’s election.