Sometimes you have to fight to preserve progress:
The lawsuit argues that the final Safer Affordable Fuel-Efficient Vehicles (SAFE) rule stops progress that has been made to protect the environment and reduce greenhouse gas emissions, hurts the economy, and harms public health.
“The Trump administration’s new rule undoes hard-earned progress to protect our health, environment, and economy,” said Attorney General Josh Stein. “As Attorney General, I will fight to uphold the law and safeguard the air we breathe and the water we drink.”
"Hard-earned progress" is right on the money. The U.S. Supreme Court had to (literally) order George W. Bush's EPA to regulate vehicle emissions in 2007, and they fiddled around until Obama's EPA started genuinely working on it. But here's the kicker: auto makers responded to both the emissions regulations and CAFE Standards (MPG), and vast improvements were made in both areas. Traffic still backs up around LA, but most of the smog is gone. In other words, everybody's happy, except the anti-government ideologues. This is what we're dealing with: