U.S. climate action received support yesterday from four former EPA administrators who served Republican presidents. William D. Ruckelshaus, Lee M. Thomas, William K. Reilly, and Christine Todd Whitman testified before the Senate’s Environment and Public Works Committee at a hearing entitled “Climate Change: The Need to Act Now.” They delivered a clear message for Congress: Climate change is one of the greatest threats to America’s economy, environment, and communities—and it need not be a partisan issue.

Indeed, what was most encouraging about today’s hearing was authoritative Republican voices calling for climate action, something presently missing from much of the debate in Congress today. In recent years, the issue of climate change has moved from one of reasonable debate about how best to address threats, to one where sharp partisan lines have been drawn, making it difficult to make progress. But as today’s hearing demonstrates, this was not always the case—and need not be the case in the future.

A History Lesson on Environmental Action

The EPA was created under President Nixon, with Ruckelshaus serving as the first administrator. As the four administrators said, the agency faced resistance from what Ruckelshaus called “powerful economic interests,” with opponents arguing that environmental initiatives would destroy jobs and the economy—similar to what critics of climate action say today. Yet the EPA still made enormous progress thanks to bipartisan support—decades later, we can see the environmental and economic benefits. “From 1980 to 2012, total emissions in the United States of six common air pollutants dropped by 67 percent,” said Whitman, EPA administrator under President George W. Bush. “At the same time, our population grew by 38 percent, our energy consumption increased by 27 percent, and our GDP more-than-doubled.”

Today’s witnesses made clear that if history is prologue, we can take bold action to address climate change, show leadership, and strengthen our nation and economy as we do so.

The Costs of Climate Change Inaction

“The models of the world’s leading scientists predict rising seas, drought, floods, wildfires, and more severe and frequent storms,” said Ruckelshaus, who is also a WRI Board member. “We are seeing impacts already.”

He pointed to the Puget Sound, where coral bleaching threatens the region’s $275 million shellfish industry. Thomas, who headed the EPA during the Reagan administration and is also a WRI Board member, highlighted his home state of Florida, where sea level rise overwhelms drainage systems and infiltrates the drinking water supply of coastal towns. Reilly, President George H.W. Bush’s environment administrator, discussed his role on California Governor Arnold Schwarzenegger’s task force, which determined that 1,100 levees in the Sacramento Basin simply won’t survive projected sea level rise. And New York, Boston, New Orleans, and other communities face similarly expensive threats from a warmer world.

“The economic impact is undeniable,” Thomas said. “Local governments struggle to address today’s impacts of climate change while trying to anticipate the increased risk it poses in the future.”

The Benefits of Climate Change Action

Tackling climate change now can not only prevent some of the more costly and “draconian impacts later this century,” as Reilly said, but it can also generate economic benefits.

Take the newly announced U.S. power plant emissions standards, one of the most significant actions the country has taken to reduce carbon pollution. Power plants are the single-greatest source of U.S. greenhouse gas emissions, representing roughly one-third of the total. As Senator Sheldon Whitehouse noted, the EPA’s proposed power plant rules would produce $93 billion in public benefits each year by 2030.

WRI analysis finds that a number of states are already in a good position to comply with the new power plant standards through existing infrastructure opportunities and current energy targets. Indeed, evidence shows that curbing power plant emissions through increased renewable power generation and efficiency can reduce costs for states, consumers, and utilities. For example, Michigan’s energy efficiency standard saved the state $1 billion in its first three years. Another study found that reducing Tennessee’s energy usage by 6.6 percent by 2020 would generate $1.6 billion in electricity savings in that year, with the average household saving $264 on their annual energy bill.

As the testimony yesterday underscored, we have tackled complex environmental issues in the past, and we’ve done so with bipartisan support while increasing GDP and growing our economy. As evidence shows, the country can’t afford not to pursue ambitious climate action.