In the preceding decades, the attributes of climate change—including long time horizons, complex science, numerous and widespread contributors, and disparate geographic impacts—repeatedly intersected with political and legal processes to frustrate the development of effective mitigation laws and policies. Climate change thus lives up to its billing as a “super wicked” public policy problem defying ready solution.1 Current commitments by countries to reduce atmospheric greenhouse gases (GHGs) fall far short of what is necessary to limit climate change and its impacts to tolerable levels. Even if every party honors its non-binding commitments under the Paris Agreement, models project that warming will, within this century, significantly exceed 2°C, the level of warming generally recognized as the maximum tolerable.2 To put this in perspective, the present-day manifestations of “just” a little over 1°C warming—wildfires, flooding, storms—are proving to be deadly, costly, and dislocating; as discussed in the next chapter, scientists project even more serious, irreversible impacts with warming of even 1.5°C. Yet knowledgeable observers caution that “barring rapid global political, social, and technological transformations … we will be fortunate to limit temperature rise to 2.6°C, just as likely to reach 3.9°C, and the possibility of reaching 4.0°C or higher cannot be ignored.”3