In recent weeks, it has become inescapably obvious: The mania for muzzling how teachers address race and other topics is only accelerating.

We’re seeing dozens of GOP proposals to bar whole concepts from classrooms outright. The Republican governor of Virginia has debuted a mechanism for parents to rat out teachers. Bills threatening punishment of them are proliferating. Book-banning efforts are outpacing anything in recent memory.

Amid this onslaught, a proposed bill now advancing in the New Hampshire legislature deserves renewed scrutiny. It would ban the advocacy of any “doctrine” or “theory” promoting a “negative” account of U.S. history, including the notion that the United States was “founded on racism.”

Additionally, the bill describes itself as designed to ensure teachers’ “loyalty,” while prohibiting advocacy of “subversive doctrines.”

This proposal is drawing heightened attention from teachers and their representatives. With the push for constraints on teachers intensifying, they worry that if it succeeds, it could become a model in other states.

“It’s the next step in their campaign to whitewash our history by rewriting it,” Megan Tuttle, the president of the New Hampshire chapter of the National Education Association, told me in a statement.

If this passes, it will “stifle real discussion" in classrooms, Tuttle said, adding: “Then it’s only a matter of time before similar legislation has the same impact on classrooms around the country.”

This proposal opens a window on much of what’s wrong with the current wave of censoring panic. Many new proposals and laws are sloppily drafted, vaguely defining entire concepts off limits, such as “anti-American ideologies” or anything that deviates from undefined conceptions of the nation’s “authentic founding.”