Just in the nick of time, U.S. Transportation Secretary Anthony Foxx on Monday announced that the federal government will have an online registration system in place for drones before thousands of Americans unwrap new ones Christmas morning.

That's a relief. The past few months have been filled with reports of careless drone operators endangering the public by not following crucial rules about the use of U.S. airspace. Having a database of drone registrations will help authorities track down people who use their aircraft irresponsibly or maliciously. Another bonus: It's a good opportunity to pass on crucial information about where to fly — and not to fly.

This is no time for federal authorities to relax, however. Building a registration system is meaningless if no one knows about it. That raises a real concern about how to get the word out to hundreds of thousands of people by Monday, when everyone with a drone that weighs more than a half a pound will be required to register with the Federal Aviation Administration, pay a $5 fee and affix a tail number to the drone.

Foxx was smart to bring together the associations representing drone manufacturers and users in October to help draft the recommendations that led to this week's rule. Although these groups were not completely satisfied with the outcome — the nominal registration fee is a particular issue because of the concern that it will stop compliance — they will no doubt convey the new requirement to their members.

Even if they do, however, that still leaves thousands of people unaware. And though the FAA can impose hefty civil or criminal penalties on people who don't register, let's be honest: No one's going to be rounding up scofflaw owners and dragging them to jail for failing to put a tail number on their toy drone. Nor should they. Having a drone should not be a crime.

But we do want people to register, and a voluntary system may not accomplish that. Who would bother to register their car if wasn't compulsory? Sooner rather than later, the FAA must consider requiring drones to be registered where they are sold so that it becomes automatic. With more than 1 million drones in the hands of users, many of them novices with little appreciation for the damage they can cause, the public shouldn't be left guessing who owns the drone that crashed into their property or violated their privacy — or worse.