In the background during President Trump's swing through California on Tuesday was his administration's plan to kill the state's authority to set tailpipe emission standards.
A formal announcement is reportedly set to happen at the Environmental Protection Agency headquarters in Washington, D.C., on Wednesday.
This is the big environmental fight between California and the Trump administration that has been anticipated for months. (Not to be confused with the scores of other environmental fights between said parties.)
State Attorney General Xavier Becerra has another lawsuit ready to go, judging by the Twitter chest-thumping.