It is no secret that, as the radical left moved from protesting on campuses in the '60s to infiltrating those campuses as educators in the decades since, American colleges and universities have been fundamentally transformed from institutions of higher learning to mills of political indoctrination. Through the left-wing schools of education and activist figures like terrorist Bill Ayers — a "distinguished professor of early childhood education" and editor of a series of manuals on teaching "social justice in secondary schools — the tentacles of that indoctrination now latch onto youthful minds beginning in kindergarten.

By the time today's young college arrivals first unpack in their dorms, they are shoddily educated but already steeped in left-wing propaganda. They can barely read, have no appreciation for our country's past except what anti-Americanism they have absorbed from communist historians like Howard Zinn, and are utterly ignorant of civics and the Constitution. But they have been steeped in social justice ideologies that see the world through the Marxist lens of victimhood and oppression. Make that white male capitalist oppression.

In an incident typical of the new pedagogy, a Staten Island sixth-grader came home last month with a politicized vocabulary assignment that disparaged Republican President Trump while praising his Democratic predecessor Barack Obama.

In Maryland last year parents sued a school district for requiring that its high schoolers write and recite the Islamic profession of faith, while no such requirement existed — or could exist — for reciting the Lord's Prayer, since that would allegedly violate the separation of church and state. Immersing students in Islamic faith is routine, of course, in California schools. In Maryland the schools spent two weeks studying Islam as opposed to a single day spent learning about Christianity or Judaism. This imbalance in religious instruction has become a common theme across the United States today as educators promote a rosy-eyed version of Islam.

This year Washington State schools will begin implementing new health and physical education standards that require students to learn about "gender identity" and "gender expression" beginning in kindergarten.

Last January an activist group within the Philadelphia Federation of Teachers called the Caucus of Working Educators launched an optional lesson plan for the city's kindergarten-to-12th grade students that included six days of social justice action. From "The Revolution Is Always Now" coloring pages for the younger kids to a science lesson about the biology of skin color for the older ones, the focus was on imbuing children with a heightened awareness of alleged racial inequalities and white privilege, fostering feelings of resentment and guilt.

That curriculum urges teachers to base lessons on the 13 tenets of the racist Black Lives Matter movement's agenda, which include "Restorative Justice," "Globalism," "Unapologetically Black," and "Collective Value." Teachers were also encouraged to wear Black Lives Matter T-shirts — a pedagogical mandate that immediately spread to schools in Seattle as well.

Some Philadelphia teachers rightly objected to such blatant politicization in the classroom. "I don't think kids should be taught that Western society is perpetrating a war on black people," said one English teacher. The president of a Fraternal Order of Police chapter also spoke out. "We think there's a lot better subjects that could be taught," he declared. But the black supremacist doctrines of Black Lives Matter ruled the day.

Cautionary voices are ineffective in countering the classroom influence of overwhelmingly left-wing teachers at every level across America who view their mission not as teaching students how to think, but telling them what to think. This is the antithesis of what education in a democracy has always been. Its model is the curriculum of schools in totalitarian societies and its bible is the totalitarian educational handbook Pedagogy of the Oppressed by the Brazilian Marxist Paulo Freire. Too many K-12 teachers and their unions see the schools as a platform for their anti-American, anti-white, pro-Marxist political agendas packaged as "social justice" activism.

The deep divisions we face as a nation have their roots in the transformation of our schools into indoctrination and recruitment centers for the political left. It is long past time that we addressed their perversion of our educational system into a radical political platform. It is a violation of the trust we have traditionally placed in the hands of the nation's teachers, and it needs to be remedied by a code of ethics that restores traditional nonpartisan attitudes to our classrooms.

We have proposed a Code of Ethics for K-12 teachers that enforces and restores the traditional approach to a democratic education, which is that children are in school to be taught how to think, not — as in authoritarian and totalitarian societies — to be told what to think. There is no political orthodoxy in America but tolerance for diverse viewpoints, and that is the educational orthodoxy that must prevail.

David Horowitz is founder of the David Horowitz Freedom Center and author of Big Agenda: President Trump's Plan to Save America.
Mark Tapson is a Shillman Journalism Fellow at the Freedom Center. @MarkTapson