It's often said that bad facts make bad law. In the case of the Ninth Circuit's just-issued ruling continuing the nationwide injunction against Donald Trump's executive order pausing immigration from seven jihadist or jihad-torn countries, it's necessary to amend that saying. Bad facts combined with superheated politics can make terrible law.
Before addressing the court's ruling, let's refer back to some of the bad facts that made it more likely. Critically, the Trump administration issued a significant executive order (and then defended it in court) without laying any real factual foundation for its finding. Next, the administration enforced the order in a haphazard and unnecessarily cruel manner, initially including even green-card holders in its scope. By slamming the door (at least temporarily) in their faces, it created a crisis atmosphere that not only ramped up the political stakes, it told the court that the administration didn't exactly know how to interpret its own order. This invites judicial meddling.