This Earth Day, we’d like peace on the planet and goodwill among environmental regulatory agencies.

Sometimes, the latter seems more realistic than the former.

Maine and many other states are again taking the Environmental Protection Agency to court, this time for failing to comply with a Supreme Court ruling giving the EPA authority over automotive emissions under the Clean Air Act.

Squabbles between the state and federal agencies are nothing new. Maine and the EPA have been at legal loggerheads for more than 25 years now. Recent notable chapters include actions on greenhouse gas and mercury emissions, in which Maine has twice triumphed.

Which is the key point – at most turns, when states have challenged the EPA to fulfill its regulatory and statutory requirements, federal courts sided with the states. In some cases, it took years for these decisions to emerge.

When they did, a pattern of weak enforcement of important federal environmental regulations became clear. The courts are not upholding state complaints because of federalist solidarity, but because their arguments are correct.

A prime example is this latest court action. The Supreme Court has told the EPA it can develop rules for managing carbon dioxide emissions from automobiles, which the agency hasn’t addressed. Of course, developing regulations for emissions is not an overnight project.

Plaintiff states, however, are still pressing the EPA anew, not because they don’t recognize the complexity of the issue, but because there’s little confidence among states that the EPA will act without prodding from the courts.

About 25 years ago, former Maine Attorney General Jim Tierney said it was “Orwellian” to think states should sue the federal government to enforce its environmental laws. Now, these actions have become almost routine.

How this protects the planet is anyone’s guess.

So for the good of the planet, this adversarial relationship between the states and EPA cannot continue. Public concern about the environment is arguably at its peak, driven by fears of dwindling resources and climate change.

We are becoming an environmentally sensitive society. Sales of hybrid vehicles are rising, as more manufacturers offer alternatives. Even the stalwart plastic grocery bag is under assault as an environmental offender.

Wags might call this “greenwashing.”

In our view, it’s not that cynical. While phrases like “green” and “sustainability” are nice buzzwords, the significant change is more and more, we, as a people, are considering the environmental impact of our actions as second-nature.

Yet, from a regulatory perspective, discord reigns. The next president must change the EPA’s perception from obstacle to advocate, and foster cooperation – not more fights – with states. Jigsaw approaches to broad environmental regulation are no replacement for clear and stringent federal guidelines.

As an agency with an important future role in policy and society, the EPA’s credibility must be rebuilt.