The recent debate about Harriet Tubman replacing Andrew Jackson on the front of a $20 bill revealed broad disagreements in the country about the value of lifting up the contributions to the nation made by women and people of color.

It also revealed the importance of being properly educated in American history.

We’re used to seeing history curriculum being altered by religious fundamentalists and conservatives to impart false ideas to schoolchildren.

In Texas, state school board members recently issued geography, history, and U.S. government textbooks that pushed conservative Christian fallacies about U.S. history, including warped views of Biblical influence on the nation’s founders and the importance of slavery as the chief cause of the Civil War.

In Colorado, school board members in a district outside of Denver made national news when they rejected a highly regarded history curriculum because it didn’t sufficiently “promote citizenship, patriotism, essentials and benefits of the free-market system, respect for authority, and respect for individual rights.”

But at least those controversies took place in public, so opposing points of view could respond.

The Texas textbooks caused such a storm that a publisher of one of those books, McGraw-Hill, was forced to issue an apology about a caption in the book that referred to African slaves who were forcibly brought to the Americas as “workers.” The textbook controversy prompted California lawmakers to introduce a bill in the state legislature to prevent Texas-approved changes from seeping into textbooks in the Golden State.

In Colorado, the actions of the conservative school board caused mass student walkouts in high schools across the district, and local parents organized a successful effort to kick the offending board members out of office.

American history school curriculum has been a subject of heated debate forever, and indeed it should be, as history stays alive by reflecting on and then reconsidering whose point of view the narrative comes from.

But what if the debate, instead of taking place in the public, is completely hidden from view?

That’s the question members of Congress need to consider this week as they deliberate over a bill to renew funding for a school voucher program in Washington, D.C.

The Fad Over School Vouchers

As an article in The Washington Times explains, the “Opportunity Scholarship” voucher program gives low-income students in the District the opportunity to transfer from public schools to private schools at taxpayer expense. Conservative Republicans champion the program as a “promising new pathway” for children out of “failed” public schools. It’s one more way the District – lacking the autonomy of a state – is used by congressional conservatives as an ideological plaything, in disregard of the will of District residents.

The Obama administration, which has declared it will not veto the bill should it pass the House, nevertheless opposes the vouchers because they don’t produce any statistically significant results for the children who use them.

As I reported for Salon in 2014, school vouchers – which are frequently disguised with euphemistic terms such as scholarships or tax credits – have long been dismissed by liberals, yet their presence has significantly increased in state and federal education policy.

These programs are now prominent features in education policies in about a third of the states in the country, siphoning billions of dollars from public service budgets.

Most recently, a voucher program passed in Nevada, according to Education Week, that would allow all parents of public school students to “use state funding earmarked for their child toward tuition or other expenses related to a nonpublic education.” The law is currently tied up in court, but according to a report in The Washington Post, prominent conservatives, such as former Florida governor and failed presidential candidate Jeb Bush, are already trying to push the Nevada voucher program nationwide. “Lawmakers in Georgia, Iowa and Rhode Island considered similar legislation this year,” the Post reporter explains.

Track Record On Vouchers Mostly Negative

There is a long track record of failure for vouchers, particularly in Milwaukee, where a 26-year program has produced little gains for the students who’ve have taken advantage of more than $1.7 billion in taxpayer money to transfer to private schools. Even more significant, the voucher program has done nothing to lift up the entire system.

An analysis last year of a long-running statewide voucher program in Louisiana found “harms students’ academic performance,” as reported by U.S. News & World Report.

The D.C. voucher program has had more mixed results producing “no conclusive evidence” in overall achievement for the students who participated but significant improvement in high school graduation rates.” Although it can be argued that the quality of education in the District has improved of recent, the D.C. schools as a whole continue to produce some of the most unequal results in achievement between white students and their nonwhite peers.”

Most of the war over voucher programs is fought over quantifiable data about the academic results these programs hardly ever seem to produce and the money they redirect from public schools to private pockets.

But there is an important quality issue as well.

How Vouchers Promote Religious Schools

First, there is the issue of church and state separation. All research shows that most of the money voucher programs redirect from public schools to private institutions ends up going to religious schools. In D.C., 80 percent of voucher users attend religion-based private schools. North Carolina’s relatively new voucher program sends 93 percent of its money to “faith-based schools.”

Due to voucher programs, in all their forms, “religious schools actually are receiving large amounts of government money,” David Berliner and Gene Glass explain in their book “Myths & Lies that Threaten America’s Public Schools“.

Berliner and Glass explain how, through various workarounds approved by ideologically driven courts, many states have reversed historical precedent to ensure the public is unwittingly funding religious-based instruction. In Arizona, a tuition tax credit program ensures that people and corporations who donate to a fund for private, mostly religious, schools can take that donation off their taxes, which decreases the amount of money the state has to spend on public services. In Ohio, government funds pay directly for parents’ tuition payments in private schools, most of which are religion-based. In New Jersey, the governor enjoys a special set-aside of $11 million for two religious schools in the state.

In most of these cases, the majority of the students receiving voucher money were already previously enrolled in religious schools. So much for “opening promising new pathways” in the public school system.

Voucher programs that redirect money to private religious schools are in clear violation of the federal Constitution’s establishment clause and state constitutions’ Blaine Amendment language, but the programs continue to proliferate and expand nevertheless.

This Should Alarm Every American

As Berliner and Glass explain, “Diversion of existing public schools resources to private schools results in taxpayer support for all kinds of religious instruction at all kinds of religious schools, with little or no oversight by states or the public.”

That means public tax dollars are funding religion-based curriculum that teach, for instance, a creationist view of science or a version of history that portrays slaves as happy servants to their masters. (One of the recipients of D.C. Opportunity Scholarship vouchers is the Calvary Christian Academy, which serves a predominantly African-American student body. As Isaiah J. Poole wrote in 2014, it has used history books that reject “the Marxist/Hegelian conflict theory of history in favor of … positive, uplifting history texts”; math textbooks “not burdened with modern theories such as set theory,” which happens to be heavily used in statistics and computer science; and science texts that “teach that modern science is the product of Western man’s return to the Scriptures after the Protestant Reformation” and refute “the man-made idea of evolution.”)

Curriculum materials that depict people of color in demeaning, stereotypical waysthat have created such consternation in public schools can be readily adopted for private schools using vouchers. And how many schools getting voucher funding will choose a right-wing version of history that teaches the founders of the nation never intended the separation of church and state but sought instead to construct a Christian theocracy?

Voucher proponents claim all of this is fine because parents have “made the choice.” But shouldn’t we have a choice about whether or not we fund this?

Most Republicans running for president have come down firmly on the side of embracing more “choice” in education, including vouchers.

GOP front-runner Donald Trump’s education policy ideas are sill largely a mystery. But his perspectives on American history are pretty obvious. When questioned about the decision to replace Andrew Jackson with Harriet Tubman on the $20 bill, Trump replied, according to the Wall Street Journal, he’d prefer to keep Jackson on the 20 and put Tubman on the $2 bill instead.

But then again, Trump is also on record declaring, “I love the poorly educated.” Should the craze for school vouchers continue, Trump may get just the kind of electorate he prefers.