Battle lines are drawn over Trump's weakening of emissions rules

The response to the Trump administration's final rules weakening vehicle mileage and emissions standards through the mid-2020s offers a hint of the shifting plates in the industry and the battles ahead.

Why it matters: The prior rules were a pillar of the Obama-era climate agenda, and transportation is the nation's largest source of greenhouse gas emissions.

• In a sign of the weight and intensity of the fight, former President Obama took what Axios' Ursula Perano points out is the rare step of publicly rebuking the administration.
• And the White House last night released a statement hailing the rules for giving a "reality check to radical Green New Deal environmental activists" and "delivering the largest deregulatory action" of Trump's tenure.

Catch up fast: Reuters has an excellent piece on yesterday's joint EPA and Transportation Department announcement of rules that run through model year 2026. The upshot is that they require 1.5% annual efficiency gains, compared to 5% under the prior mandate.

• The administration says the rule will "result in about 2 billion additional barrels of oil being consumed and 867 to 923 additional million metric tons of carbon dioxide being emitted and boost average consumer fuel costs by more than $1,000 per vehicle over the life of their vehicles."
• But, but, but: "The administration said the revised rules will cut the future price of new vehicles by around $1,000 and reduce traffic deaths. Environmentalists dispute that the rule will reduce traffic deaths," Reuters reports.

The intrigue: The responses offer a window into the tensions within the auto industry.

• Most of the industry thought the Obama-era rules had become infeasible, but from there, things get more confusing and scattered.
• In a sign of those internal disputes, the Alliance for Automotive Innovation, which is the industry's main trade group, yesterday declined to offer a firm position.
• The group instead said it's "carefully reviewing the full breadth" of the rule to gauge how much it supports their various market, consumer and environmental priorities.
• Another sign of industry divisions: Volvo yesterday said it's joining the preliminary agreement California reached last year with Ford, VW, BMW and Honda to meet tougher standards for its nationwide fleet than the Trump plans require.

What's next: Litigation. California and states that follow its lead on emissions are certain to sue, and so will environmental groups.