Will the Paris Agreement Survive Without the U.S.?

The Paris Agreement remains the cornerstone of global climate action, uniting nations in the fight against climate change. However, with the U.S.—the world's second-largest emitter—having previously withdrawn and facing ongoing political uncertainty, one pressing question remains: Can the Paris Agreement survive without full U.S. participation?

The answer is yes, but not without consequences. While the Agreement is resilient, losing the full backing of the U.S. weakens its overall impact and global momentum. Yet, despite shifting federal policies, a significant portion of the U.S. remains committed to Paris-aligned climate goals.

The U.S. Climate Alliance: A State-Level Commitment

One of the most compelling responses to federal disengagement from climate policy has been the rise of state and local action. The U.S. Climate Alliance, a bipartisan coalition of 24 states that remain committed to meeting Paris Agreement goals, represents 54% of the U.S. population and 57% of the country’s economy.

This coalition proves that climate action in the U.S. isn’t solely dependent on federal leadership. Instead, state and local governments, businesses, and communities have stepped in to drive progress where national policy has stalled. Their efforts ensure that the U.S. remains a significant player in reducing global emissions, even in the absence of a unified federal approach.

Case Study: Wisconsin’s Climate Progress and Roadblocks

To understand how state-level action plays out in practice, we can look at my home state of Wisconsin, which joined the U.S. Climate Alliance in 2019 under the leadership of Governor Tony Evers, who now serves as an executive committee member.

Wisconsin has made progress, but not at the pace needed to meet Paris targets. According to Wisconsin Public Services and the State Climate Policy Dashboard:

• Renewables make up 17% of the state's energy mix, with hydroelectric power leading the way.

• Net greenhouse gas emissions dropped 15% between 2005 and 2021, a step forward but still short of the state’s 26% reduction goal by 2025.

• Key sectors like transportation and industry remain largely untouched by bold policy changes, a likely result of partisan gridlock in the state legislature.

  
  

This underscores a larger issue: state-level commitments help bridge the gap, but without stronger federal action, progress remains uneven and often insufficient.

A 1.5°C Target That Feels Increasingly Out of Reach

The Paris Agreement aims to limit global warming to 1.5°C above pre-industrial levels, yet this goal is becoming more of a symbolic rallying cry than a realistic target. Reports from the IPCC and IEA suggest that, without drastic global emissions reductions, we are on track to exceed 2°C—bringing more extreme weather, sea level rise, and ecosystem disruptions.

What’s Next?

The survival of the Paris Agreement does not hinge on any single country. However, without full U.S. engagement, its strength is diminished. The path forward requires a dual strategy:

1. Sustained state and local leadership—building on the momentum of the U.S. Climate Alliance.

2. Federal re-engagement and stronger national policies—ensuring the U.S. can meet its commitments and push global action forward.

3. Renewed Vigor for Action in Belem - The international community will need to rally at COP 30 around their NDCs and push implementation as the US retreats from global leadership.