Should government employees be allowed to opt out of belonging to or paying a labor union? And can state governments force them to pay a union for the privilege of working?

Under the 1977 Supreme Court decision Abood v. Detroit Board of Education, the states can force them to pay, and they cannot opt out completely, although they have a can't be forced to pay for union political activities.

Abood came quite close to being overturned in 2016. The death of Antonin Scalia early that year was probably all that saved the decision. After his passing, the high court split 4-4 in the case Friedrichs v. California Teachers' Association, in which a number of teachers sued on First Amendment grounds. With Justice Neil Gorsuch now on the court, though, another case -- Janus v. AFSCME -- could finish the job.

The case was dismissed by the Seventh Circuit in March, with Judge RIchard Posner foreshadowing a likely Supreme Court showdown: "Of course, only the Supreme Court has the power, if it so chooses, to overrule Abood....neither the district court nor this court can overrule Abood, and it is Abood that stands in the way of [Mark Janus'] claim."

Over at The 74 Million, Mike Antonucci writes that teachers' unions are preparing for potentially massive losses of dues money in the event that the Janus case results in Abood being overturned. He adds the somewhat ironic point that the unions hit hardest financially could be the ones in right-to-work states. They already cannot collect forced dues (or "agency fees") from non-members, but they tend to be subsidized at the national level by the cash-generating teachers' unions in states where employees are forced to support unions, like it or not.

Various teachers unions (Antonucci gives the details) are warning their membership could decline by 20 to 40 percent if Abood is overturned. Some of them are also making downward adjustments to their 2018 budgets to prepare for the eventuality. But most of them are not, and some are in such dire financial straits that they will have a very hard time coping.

In short, teachers unions are doing something, but there is little evidence that they are prepared for the revolutionary change in their usual operations that an adverse Janus decision will bring. And time is running out.