Combating terrorism and extremism is an urgent national and global imperative. We should know. In our capacities as the director and advisory board member for the Center for the Study of Hate and Extremism at California State University, San Bernardino, which is dedicated to the study of bigotry and terrorism, we dedicate significant portions of our professional and intellectual energies to tracking the problem and working toward various solutions. In that capacity we feel duty bound to point out the serious practical, logical, and legal flaws in President Trump’s recent executive order, titled “Protecting the Nation from Foreign Terrorist Entry into the United States.”

The essence of the order, and the source of most of its deepest flaws, is found in its sweeping and all-encompassing nature. It virtually shuts the door on refugees, halting the refugee program for the next four months, and capping the total number of all refugees accepted into the United States this year at 50,000. It indefinitely bans any and all Syrian refugees from entry. It also bans almost all entry by citizens of seven Muslim-majority countries: Iran, Iraq, Sudan, Somalia, Yemen, Libya, and Syria, for at least 90 days.

No exception is made for children or the elderly, the sick or the suffering, family members of Americans, or virtually any other extenuating or humanitarian circumstances. This draconian travel ban even originally applied to U.S. permanent resident green card holders, who would have been cut off from their homes, families, and jobs here at home. A political outcry, and the evident illegality of that provision of the order, brought a quick reversal.

The order, because it is so sweeping and all-inclusive, makes no sense as a counterterrorism policy, because it treats countless millions of people as a pool of potential terrorists and assumes that U.S. government institutions can’t make rational and accurate judgments that certain visitors simply aren’t dangerous. Many Americans may assume that banning entry to all citizens of those seven countries will make us safer. There simply is no valid reason to think that.

As a candidate, Trump argued for a complete ban of the entry of all Muslims, originally including American citizens. He did that in the immediate aftermath of, and directly citing, the horrifying terrorist attack in our center’s hometown, San Bernardino. The problem is, the culprits were a U.S.-born American citizen and his Pakistani-born wife (who was a permanent resident). In neither case would either of them have been affected in any way by any part of Trump’s new order.

Moreover, since before Sept. 11, 2001, no deadly terrorist actions in the United States committed by terrorists have been committed by any citizens of the designated countries. So not only does the order exclude countless blameless individuals who have every reason, and in many cases a moral right, to come to our country; it wouldn’t have excluded or thwarted a single person who has committed a deadly terrorist act in the past 15 years, including all 19 perpetrators of the 9/11 attacks.

For those of us in, or deeply connected to, San Bernardino, and especially who additionally specialize in trying to combat extremism and terrorism, it is particularly galling and painful to see our own tragedy being cynically exploited to justify a policy that doesn’t address any aspect of that atrocity, or any other terrorist attack committed in our country in living memory. As Ryan Reyes, who lost his partner in the attack, protested, “I find it disgraceful that (Trump is) doing it because of (his) agenda. Don’t hide behind someone else’s tragedy.”

The San Bernardino killers did have a huge stockpile of weapons and ammunition. Arguably, stricter gun control legislation coupled with common sense visa waiver reforms might have addressed two aspects of their terrible crime. But the president’s new order simply doesn’t do that. As Trenna Meins, who lost her husband, Damien, in the horror, told us: “I understand what we’re trying to do, but taking drastic steps without planning is not effective to accomplish the goal of securing America.”

We strongly agree that it is appropriate to carefully and thoroughly screen all, and even prohibit some, would-be visitors, immigrants and refugees from countries that are hotbeds of extremism, designated state sponsors of terrorism or ravaged by war. But that already is in place, as ability of the existing procedures to prevent violent extremists from entering our country and killing people amply demonstrates given the relative paucity of such incidents. Of course, every single act of violence is unacceptable, and all reasonable measures to strengthen border security and immigration procedures are to be welcomed, particularly as conditions change.

But most of the provisions in this order are unreasonably sweeping, and are likely to be far more counterproductive than helpful in the fight against terrorism. To take just one example, we have just labeled all 38 million people of Iraq a pool of undifferentiated potential terrorists unwelcome in our country because we lack the ability to tell if any of them might not be dangerous lunatics. But these are the exact same people we are relying upon as our primary ground forces and principal allies in President Trump’s own foreign policy “highest priority” of defeating the so-called Islamic State of Iraq and Syria (ISIS).

The order bars entry of not merely suffering Syrian men, women, and children, but also the very Iraqis we are asking to fight and die in what amounts to our most important war. People who have known and worked with our military for years, who are the biggest enemies and the greatest victims of ISIS and other terrorist groups, are all thrown into the same category as their enemies and victimizers by this reckless proclamation. We know this first hand as one of our young criminal justice students, an Iraqi refugee himself, recounted this week how the brutality he experienced in Iraq shaped his view of his new home: “I would die for this country because this country gave me the education and fundamental freedoms that most Iraq refugees would risk their life for.”

How do we imagine others will now react, and how will these new policies shape their view of us? And why should we care? To ask those questions is to answer them. Radical Islamist terrorist groups, on the other hand, will be delighted, finding in the order written confirmation of their narrative about “Islamophobic” American policies and a hatred of all Muslims by Americans and the West. Those claims just got much harder to refute.

So, if this doesn’t make any sense from a counterterrorism perspective, what informs it? Unfortunately, President Trump’s own rhetorical history suggests a strong bias against Muslims. So does that of his national security adviser, Michael Flynn. His chief adviser, Stephen Bannon, has a long history of wide-ranging bigotry and white ethno-nationalist demagoguery, and, while all presidents have a right to the advisers of their choice, it is deeply alarming that Trump has placed Bannon at the center of policy-making in the National Security Council. Bannon is also a leading promoter of Islamophobic hate-speech, something former CIA director David Petraeus warned “will compound the already grave terrorist danger to our citizens.”

The order itself is not exactly a “Muslim ban,” because it applies only to refugees and the citizens of seven countries. But it is clearly discriminatory and anti-Muslim in both its intentions and impact. Former New York Mayor Rudy Giuliani, a key Trump adviser, recently explained to an interviewer that Trump asked his campaign to find a way to make his proposed “Muslim ban” legal despite constitutional prohibitions against religious discrimination. This is, in effect, what they came up with.

The greatest fear is that if these policies become entrenched and extended they will be a first step. More countries can be added, smaller numbers accepted, and the walls of fear and the moats of hatred surrounding Trump’s dystopian new Fortress America will slowly begin to turn us into everything our worst enemies have, until now completely falsely, accused us of being. It is a moral and political tragedy, a legal and constitutional sleight of hand, and a counterterrorism disaster.

Brian Levin is the director of the Center for the Study of Hate & Extremism and professor of criminal justice at California State University, San Bernardino.

Hussein Ibish is an advisory board member of the center