Censorship functions as a deadly weapon in the arsenal of authoritarian regimes. Consider this:

On Feb. 14, Craig Trainor, the acting assistant secretary for civil rights in the Department of Education, disseminated a directive to public and private educational institutions across the country — preschools, as well as elementary and secondary ones, colleges and universities. That missive, in the form of a “Dear Colleague” letter, threatened to cut off all federal funds if the educational institution did not immediately dismantle and destroy any and all diversity, equity and inclusion programs.

The DOE letter is vague. Its vagueness matters and is pernicious. No person or institution could possibly know when a lecture, lesson or a program is crossing the line of what Trump is saying they can’t say or do. Part of the reason for the vagueness and ambiguity is that there is no definition of a DEI program.

The result is a chilling effect and self-censorship. Censorship in the service of racism is particularly pernicious.

The DOE directive claims that “DEI programs … discriminate in … insidious ways.” DOE alleges that they “teach students that certain racial groups bear unique moral burdens that others do not.” The “Dear Colleague” letter also claims that DEI programs “deny students the ability to participate fully in the life of a school.”

But diversity provides an educational benefit, and equity and inclusion are noble goals. Even the Supreme Court noted these benefits in its decision that nonetheless prohibited race per se being used as a criterion for college admissions.

The Dear Colleague letter denigrates and castigates DEI programs. So let’s spend a minute on our history while we still are allowed to.

Our Constitution, adopted in 1788, specifically permitted importing slaves for the next 20 years, until 1808. It put no time limit on buying and selling Black human beings already here and their offspring.

A question for Mr. Trainor: Is it permissible to teach these facts in school? May a teacher or student passionately object to the roots and branches of the racist underpinnings of the United States, both economic and political?

Apparently no educator or educational institution dare tread on this ground. Trainor asserts (citing no evidence) that “educational institutions have toxically indoctrinated students (really, he says that) with the false premise that the United States is built upon ‘systemic and structural racism.’”

Back to our history. The Constitution, in order to give slave states more power in Congress, counted each enslaved human being as three-fifths of a person. The Constitution and later the Fugitive Slave Act provided that fugitive slaves must be returned to their owners. The Constitution also empowered Congress to fund militias to put down slave rebellions.

Noteworthy, the Constitution, employing euphemisms and linguistic subterfuge, never uses the word slave or slavery. The Founders did not want to make their racism explicit for their posterity.

Approximately four score years later, the country fought a bloody civil war to end slavery. But forms of slavery persisted. Black Americans were confronted with the Black Codes and then Jim Crow. Congress didn’t pass a comprehensive civil rights law, voting rights act and fair housing legislation until the 1960s. And much of the promise of those laws still remains unfulfilled.

Would it be permissible to have a high school or college club that condemns the continuing racism that the administration is helping to perpetuate?

Fortunately, the Trainor diatribe against DEI is not a done deal. On March 5, the National Education Association sued in New Hampshire federal court to enjoin it. Numerous legal grounds undergird the challenge.

First, a governmental prohibition must be clear. No person or institution can be punished for not following a rule or law so vague that reasonable people cannot decipher its meaning. Adequate notice constitutes a foundation of due process. This directive, which demands excision of DEI efforts without a clear statement of what they are, grossly violates that constitutional guarantee.

In addition, many federal laws, including the Department of Education Organization Act, the General Education Provisions Act and the Every Student Succeeds Act, prohibit the department from inserting itself into curricular decisions — from depriving local school systems of their right to determine students’ course of study.

Yet that’s exactly what it’s doing here. After Trump, as expected, destroys the Department of Education, he will assign some other agency the task of implementing the Trainor template. The administration will continue to demand that its ideology be imposed on education and educators.

There’s another legal problem. The directive blows up longstanding DOE policies, legal positions, and guidance. Before an agency implements such a sea change, the Administrative Procedures Act requires that the public be given notice and the opportunity to be heard. None of that has happened.

Most important is the way in which the directive will destroy core First Amendment freedoms and values for both teachers and students. This policy proscription is one of the ways the Trump administration is seeking to create a government-controlled monolith of alternative facts masquerading as truth. It’s a jingoistic, whitewashed version of the country and the world, a brave new MAGA world.

Bill Newman, a Northampton-based lawyer and co-host of Talk the Talk on WHMP, writes a monthly column.