A U.S. Court of Appeals on Wednesday ruled that the Affordable Care Act's individual mandate is unconstitutional, but ordered a lower court to take a fresh look at how much of the rest of the law should fall along with it.

What's next: This decision will likely keep the ACA's protections for pre-existing conditions in legal limbo well past the 2020 election.

The intrigue: Republican attorneys general have argued that congressional Republicans’ 2017 tax law, which nullified the ACA's individual mandate, made that policy unconstitutional.

A panel of the 5th Circuit Court of Appeals said Wednesday that it agrees.

Republicans, and the Trump administration, have said the courts should strike down the entire law along with the mandate.

The 5th Circuit wrestled during oral arguments over how much of the law to strike down, ultimately deciding to kick that question back to the lower court for a new hearing. That lower court previously said the entire law would have to go.

Yes, but: The individual mandate is now essentially toothless, and it turned out not to be particularly effective when it was in effect.

So if the court is inclined to strike down the mandate alone, letting the rest of the law stand, that would be a much safer proposition than it appeared to be in 2012.

Go deeper: Government funding bill deal will repeal key ACA taxes