President Obama should not have had to explain to the Republicans who would be president that one of the basic premises of the American experiment is that this country does not apply religious tests in establishing programs and policies, regulations and rules. Yet, after Jeb Bush and Ted Cruz began peddling proposals to discriminate against Syrian refugees based on faith traditions, the president had to do just that.

“That’s not American,” declared Obama during a press conference at the G-20 meeting in Turkey. “That’s not who we are.”

Obama is right, morally and constitutionally. And he should keep stating and restating his point as a counter to the rising cry from prominent Republicans for exclusion and discrimination.

In the aftermath of Friday night’s terrorist attacks in Paris, amid reports that one of the assailants entered Europe with Syrians fleeing violence in that country, prominent Republicans have been arguing that the United States must block Syrian refugees from entering this country. Several of these Republicans have proposed that Muslim refugees should be barred, while Christian refugees should be admitted. One of them, former Arkansas governor Mike Huckabee, declares, “The No. 1 job of the president is to protect America, not protect the reputation of Islam.”

This politics ignores the diversity of Islam.

It also ignores realities on the ground in Syria, along the reality of the American experiment.

Never mind that Muslims have been primary targets and victims of Islamic State violence and oppression in Syria—and that they have suffered profoundly from the general chaos that has developed in that country. Never mind that Muslims and Christians are fleeing Syria to escape the sort of carnage that Paris has now experienced.

More than two dozen Republican governors (and at least one Democrat) are now saying that their states do not want to accept Syrian refugees. Top congressional Republicans want to upend programs that have been developed to assist in the resettlement of refugees. And Republican presidential contenders are openly calling for an official policy of discrimination.

“We should focus our efforts as it relates to refugees on the Christians that are being slaughtered,” announced Bush, the brother and son of former presidents who warned against scapegoating Muslims.

Ted Cruz claimed that it would be “lunacy” to allow Muslim refugees into the United States. “We can’t roll the dice with the safety of Americans and bring in people for whom there is an unacceptable risk that they could be jihadists coming here to kill Americans,” declared the senator from Texas. At the same time, Cruz called for admitting Christians because “there is no meaningful risk of Christians committing acts of terror.”

No one denies the threats faced by Christians in Syria. But Muslims in Syria also face threats. And just as it is reasonable to assume that resettlement programs can and will be designed with an eye toward vetting Syrian Christians before allowing them to enter the United States, those programs can and will vet Syrian Muslims.

Bush, Cruz, and their partisan compatriots understand this. Unfortunately, they have chosen to play politics. In so doing, they are engaging in the sort of scapegoating and fearmongering that America’s founders sought to guard against.

This is why Obama was so very right when he said on Monday, “We do not close our hearts to these victims of such violence and somehow start equating the issue of refugees with the issue of terrorism.”

“When I hear folks say that maybe we should just admit the Christians but not the Muslims,” Obama continued, “when I hear political leaders suggesting that there would be a religious test for which person who is fleeing from a war-torn country is admitted, when some of those folks themselves come from families who benefited from protection when they were fleeing political persecution, that’s shameful.”

“Shameful” is the proper term for the ugly political game that is being played by these Republican presidential contenders. “Some politicians have attempted to fabricate a link between the tragedy in Paris and the resettlement of Syrian refugees to the United States,” says Cecillia Wang, director of the American Civil Liberties Union’s Immigrants’ Rights Project. “Making policy based on this fearmongering is wrong for two reasons. It is factually wrong for blaming refugees for the very terror they are fleeing, and it is legally wrong because it violates our laws and the values on which our country was founded.”

Bush and Cruz have a right to make wrongheaded statements. That right is guaranteed by a Constitution that protects freedom of speech in general and outrageous political speech in particular. But the same Constitution establishes that “no religious test shall ever be required as a qualification to any office or public trust under the United States.”

This protection against a “religious test” has historically been understood as part of a broad constitutional barrier to policies that discriminate against a particular religion or religions.

To suggest that this standard might exclude any religion is, by contemporary and historic measures, absurd. Freedom of religion is an essential premise of the American experiment, put in place by founders who understood that the United States was settled by members of religious minorities who fled intolerance. For presidential candidates to now suggest that a religious test be applied to favor some religious refugees while discriminating against others neglects American history—and American values.

Adn understanding that followers of all religions are entitled to equal protection under the law, and to the equal application of public policies whether they are citizens or refugees hoping to become citizens, is the hard-wired reality of the United States.

The American history of welcoming Christians, Jews, and, yes, Muslims, is as old as the American experiment.

This country’s founders recognized Islam as one of the world’s great religions, and interacted with followers of Islam. There are records dating from as far back as the 16th century of Muslims living in what is now the United States of America. The first country to recognize the new United States was the Sultanate of Morocco (the ruler of which, Mohammed ben Abdallah, corresponded with President George Washington). John Adams referred in his 1776 essay “Thoughts on Government” to the prophet Muhammad as one of many “sober inquirers after truth.” Thomas Jefferson owned and consulted a copy of George Sale’s English translation of the Koran.

Contemporary ignorance of American history has many wellsprings. For a number of years now there has been a concerted effort by sincere if misguided religious zealots, and a parallel effort by conservative political strategists who appear to see value in exploiting fears of diversity, to redefine the American experiment as a Christian religious endeavor. History does not provide grounding for this fantasy. The founders of the country were men and women of the Enlightenment who, while surely imperfect in their thoughts and deeds, wisely sought to burst the chains of what Thomas Jefferson referred to as “monkish ignorance and superstition.” Many of the founders embraced faith traditions. But they revolted against the “divine right of kings,” rejected the construct of state-sponsored churches, and wrote a Constitution that guaranteed freedom of religion.

What Jefferson understood as “a wall of separation between Church & State” (as described in his letter to the Danbury Baptists) remains one of the great contributions of the American experiment to a world that in his time was only beginning to respect the view that “religion is a matter which lies solely between Man & his God, that he owes account to none other for his faith or his worship.”

This is not a Christian premise. This is not a Muslim premise. This is an American premise. To deny it is, indeed, shameful.

The president is right about religious tests.

“That’s not who we are.”