World leaders have been meeting in Bonn, Germany, since last week to discuss carrying out the 2015 Paris climate agreement. Sadly, though not unexpectedly, the White House and federal agencies have largely been absent from the negotiating table. But American leaders from state capitols, city halls and businesses across the country have shown up in force, and we have delivered a unified message to the world: American society remains committed to our pledge under the agreement.

Over the past two months, Americans have experienced or witnessed raging wildfires and devastating storms, from Santa Rosa, Calif., to San Juan, P.R. Warming seas, along with hotter and drier days, make these storms and fires more intense and destructive. Climate change is not a future threat; it is happening now, and we are paying for it in lost lives and billions of dollars in damage.

The United States has always led the way in confronting global challenges, especially ones that profoundly affect our own country. President Trump’s vow to withdraw from the Paris agreement by 2020 was a troubling abdication of that leadership, and it threatened to send a dangerously wrong message: that we are abandoning the pledge we made in Paris to reduce emissions at least 26 percent by 2025.

Nothing could be further from the truth. Most Americans strongly support the Paris agreement, and thousands of mayors, governors, chief executives and others stepped forward to reaffirm their commitment to it after the president walked away from the accord. Together, these states, cities and businesses constitute more than half of the United States economy and, if they were a separate country, would make up the third-largest economy in the world.