Cars in California traffic. Photo: Robyn Beck/AFP/Getty Images

The Trump administration sued the state of California Wednesday to cease its emissions trading market, arguing it's unconstitutional for the Canadian province of Quebec to be its partner.

Why it matters, per Axios' Amy Harder: This lawsuit shows the federal government going on the offense, targeting a landmark state-level climate policy that’s been in place in the Golden State for many years.

  • If it succeeds, the lawsuit could limit states’ abilities to collaborate with foreign countries on policies whose impacts don’t follow borders — like climate change.

The big picture: The lawsuit is a huge escalation of the ongoing war between the Trump administration and California, with the former having mainly fought to defend federal actions until this latest move.

  • The lawsuit claims that the cap-and-trade program, meant to help limit air pollution, is unconstitutional because a state can't have an international pact without the federal government's approval.
  • The lawsuit reads: "Allowing individual states in the Union to conduct their own foreign policy to advance their own narrow interests is thus anathema to our system of government and, if tolerated, would unlawfully enhance state power at the expense of the U.S. and undermine the U.S.’ ability to negotiate competitive international agreements."

Go deeper: Trump moves to block California from setting own auto emissions rules

Go deeper

Updated 2 hours ago - Politics & Policy

Coronavirus dashboard

Illustration: Aïda Amer/Axios

  1. Politics: Pence chief of staff Marc Short tests positive for coronavirus — COVID-19 looms over White House Halloween celebrations
  2. Health: Fauci says maybe we should mandate masks if people don't wear them — America was sick well before it ever got COVID-19
  3. World: Polish President Andrzej Duda tests positive for COVID-19.

Pence chief of staff Marc Short tests positive for coronavirus

Marc Short with Katie Miller, Vice President Pence's communications director, in March. Photo: Doug Mills/The New York Times via Reuters

Marc Short, Vice President Mike Pence’s chief of staff, tested positive for the coronavirus Saturday and is quarantining, according to a White House statement.

Why it matters: Short is Pence's closest aide, and was one of the most powerful forces on the White House coronavirus task force.

4 hours ago - World

Opposition leader Leopoldo López flees Venezuela

Venezuelan opposition politician Leopoldo López outside the Spanish embassy in Caracas, in 2019. Photo: Juan Barreto/AFP via Getty Images

Leopoldo López, a former political prisoner and prominent Venezuelan opposition leader, has left the country, his Popular Will party confirmed in a statement Saturday.

Why it matters: He's been an influential force in the push to oust President Nicolás Maduro's regime and a mentor to opposition leader Juan Guaidó. He'd been in the Spanish ambassador's Caracas residence since escaping house arrest in April 2019 following a failed military uprising.