Experts say the EPA's move to reverse the endangerment finding is dangerous for the nation. But California may have tools to weather the storm.

The agency said its 2009 finding that greenhouse gases harmed people had caused "years of uncertainty for automakers."

The proposal strikes down all greenhouse gas standards for heavy-duty vehicles and heavy-duty engines, starting with EPA’s first greenhouse gas set in 2011 for medium-duty vehicles and heavy-duty vehicles and engines.

Both SEMA and the trade group representing foreign automakers are cheering the EPA's announcement that it plans to effectively stop regulating car emissions.