Pollution is a bodily assault. Releasing a puff of smoke in a person's face is comparable to shoving a person aside while walking down the sidewalk. These are the types of behaviors that result in fights--possibly escalating to wars--and governing these interactions is one of the rationalizations for the state. As described in the Economist (A scourge of the EPA takes over at the EPA), the Trump administration has made it painfully clear that they plan to abandon environmental governance, even at a time when the majority of Americans believe that greater governance is needed (and it's not just greenhouse gases). According to that article, the demand for environmental governance really took off in the post-WWII era as a number of high-profile environmental disasters produced a bipartisan consensus is favor of the Clean Water and Clean Air acts. Even in recent years, there have been a several high-profile environmental disasters*, so how will people respond if the state abandons this realm of governance?
Some people will try to shoulder the burden themselves, treating pollution prevention as a civic duty even as profiteers exploit the opportunity to shed their waste on everyone else. But there is also a history of people enforcing their own sense of justice. However, I don't think we've ever had a situation where a large fraction of the population has desperately felt the absence of state involvement with environmental governance -- possibly leading to a form of environmental vigilantism unlike anything we've seen.
Of course, pollution is different from other forms of impositions -- the consequences are diffuse, and we all claim the right to engage in "reasonable" amounts of pollution. It is hard for vigilantees to establish a consensus on what amounts to excessive pollution, and then identify the people who create excessive pollution.
It'll be interesting to see how this develops.
* I couldn't find a list, but here are some I can think of:
- Deepwater Horizon
- Several other oil spills
- Several drinking water problems (though the immediate cause is infrastructure maintenance)
- Elk River Chemical spill of 2014