On Dec. 12, 195 countries representing about 98% of global greenhouse gas emissions approved a historic deal to rein in climate change. The agreement marks a turning point in the fight to protect future generations against catastrophic warming, and it would not have been possible without the strength of American leadership.

America’s brightest minds are charting a course to a clean energy future that will provide for our health, safety and prosperity. While some members of Congress have attempted to stall progress on climate change, their actions amount to little more than political theater. We will not abandon our responsibility to our children and grandchildren, nor will we cede global leadership on the defining issue of our time.

No single country can solve this problem alone, but the U.S. has a critical role to play in the effort to stem climate change. By vowing to cut domestic carbon pollution by at least 26% by 2025, the U.S. laid the foundation for an international agreement. In the run-up to the negotiations, the world’s largest polluters—including China, India and the E.U.—all pledged to address their greenhouse gas emissions. Their commitments will prove vital to providing for the safety and well-being of the American people. Only through a global agreement will we stem global climate change.

The American public understands this. Two in three Americans agree the U.S. should take part in an international agreement to limit global warming. Three in four support regulating carbon dioxide as a pollutant, including a majority of Republican voters.

Americans are worried about climate change because they can already witness its effects. They see its signature in the drought in California, where record heat has dried the state’s fertile soil. They see it in the remnants of Superstorm Sandy, where elevated sea levels extended the reach of coastal floods, destroying homes and inflicting billions in damages. They see it in my own state of Hawaii, where rising oceans are eroding beaches, cliffs and wetlands.

In the face of such threats, Americans have no choice but to act. California and New York are both aiming for dramatic reductions in carbon pollution by mid-century. Hawaii has set a goal of generating 100% of its energy from renewable sources by 2045, and the state working hard to limit pollution from cars and trucks as well. At the national level, we have enacted smart policies like the Clean Power Plan, President Barack Obama’s initiative to limit carbon pollution from U.S. power plants.

Americans know our only response in the face mounting risks from climate change must be the swift transition to a clean energy economy. We do not have the luxury of burying our heads in the sand.

We are a nation that prides itself on our ability to triumph in the face of overwhelming odds. When President John F. Kennedy declared that we would send an astronaut to the moon, he said that would do it not because it was easy, but because it was hard. And his words spoke to something deep in our national character, a sense that no challenge lay beyond the ingenuity and determination of the American people. It’s that very spirit that animates our fight against climate change.

We need big ideas and bold action to deal with global warming. There is no place for politicians who would surrender hope and ambition in the face danger and uncertainty. Now is the time for America to lead.

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