The problem isn't taking technical countermeasures to confound those who would link to them.

NPR is, in essence, saying that they have the right to control the contexts in which references may be made to them. It's as though NPR is saying that I can't stand on a corner with a sign saying "NPR back door this way."

The countermeasures you describe would be preferable. To extend the analogy, countermeasures would be as though NPR is admitting that I have the right to point to their office, but they can decide only to admit those who they invite in, and the only door you can come in through is the front door.

Controlling who can access your work and under what circumstances *is* part of copyright. Controlling who can make reference to your work is *not*.

NPR's dilemma is that is doesn't mind if *some* people offer directions to its back-door. It doesn't want to use a countermeasure on its site (like requiring a login and password to visitors, or a token that it hands out to people with whom it has deals for cross-linking) because that countermeasure will confound those whom they want to link to them.

That's the creator's dilemma. If I make my work available to the public, the public will see it -- including trolls and jerks and scam artists. If I want to, I can publish a novel but only sell it by mail, offering it only to people I like. That's no way to make a living, though.

If NPR wants control over access to its material, so be it. But it has to stop asserting in public that it has the right to control access to links, the public facts that are the basis of the Web.