He said the east and north was "a bit more problematical" , where routes are being checked in Edinburgh, Dundee and Aberdeen, and on the line from Perth to Inverness.

The bans are especially problematical because of their vagueness, which can lead to the stifling of even noncontroversial and undisputed history.

Prosecutions for events from 40 and 50 years ago are very problematical, as the latest developments show.

Of course, nothing prevents Mr. Biden from acting unilaterally on matters within his powers, as he has in rejoining the Paris Agreement on climate change and canceling a problematical oil pipeline from Canada.

Testing could be problematical, as could the reality that any plan advanced by baseball will have to be approved by local authorities in various states and municipalities.