As legal briefs pile up in the legal battle over the constitutionality of President Donald Trump’s executive order restricting immigration, a group of national security veterans has made a forceful case undercutting the government’s lead argument in defense of the order.

The short of it: There’s no national security justification for the president’s sweeping travel ban, which suspends all refugee resettlement temporarily and bars immigrants from seven predominantly Muslim nations. In fact, the former officials contend, his actions only leave the country worse off in the realm of foreign affairs.

“We view the Order as one that ultimately undermines the national security of the United States, rather than making us safer,” former secretaries of state John Kerry and Madeline Albright said in a signed court declaration, along with eight other former high-ranking officials who have served the national security and intelligence apparatus under both Democratic and Republican administrations.

“In our professional opinion,” continued their joint declaration filed Monday with the U.S. Court of Appeals for the 9th Circuit, “this Order cannot be justified on national security or foreign policy grounds.” The appeals court is soon expected to rule on whether to extend a temporary freeze on the ban, first imposed by a federal judge late Friday.

The filing was attached to a legal brief by the states of Washington and Minnesota, which are urging the appeals court to affirm the temporary hold on Trump’s travel restrictions until the judge assigned the case, U.S. District Judge James Robart, may consider further evidence and arguments from both sides and decide whether to extend his initial order.

Trump’s order, the officials warned, “could do long-term damage to our national security and foreign policy interests, endangering U.S. troops in the field and disrupting counterterrorism and national security partnerships. It will aid [the Islamic State’s] propaganda effort and serve its recruitment message by feeding into the narrative that the United States is at war with Islam.

“It will hinder relationships with the very communities that law enforcement professionals need to address the threat. It will have a damaging humanitarian and economic impact on the lives and jobs of American citizens and residents. And apart from all of these concerns, the Order offends our nation’s laws and values.”

Signatories to the filing include Janet Napolitano, President Barack Obama’s Homeland Security secretary during his first term; Michael Hayden, Avril Haines, Michael Morell and John McLaughlin, all formerly with the Central Intelligence Agency in various capacities; Leon Panetta, who led the CIA and later the Defense Department between 2009 and 2013; and Susan Rice, a key adviser for Obama on national security issues.

The reason these former officials’ views could be persuasive to the appeals court at this early stage of the litigation is that a key argument the Trump administration is making to reinstate the travel ban is that the president’s judgment on immigration should not be scrutinized by the courts ― in large part because Congress has already ceded the power over immigration laws to the executive branch.

“Judicial second-guessing of the President’s national security determination in itself imposes substantial harm on the federal government and the nation at large,” Department of Justice lawyers told the 9th Circuit in the emergency appeal they filed Saturday.

But the former national security officials, several of whom served under Obama until his last day in office and thus have intimate knowledge of the system Trump inherited, said the incoming administration gave no indication that it sought to overhaul the process for screening travelers who may pose a security risk, let alone that it sought the guidance of experts in the field in advance of the order.

“We know of no interagency process underway before January 20, 2017 to change current vetting procedures, and the repeated need for the Administration to clarify confusion after the Order issued suggest that that Order received little, if any advance scrutiny by the Departments of State, Justice, Homeland Security or the Intelligence Community,” the former officials wrote.

Steven Vladeck, a University of Texas law professor who co-signed his own brief against the travel ban alongside other scholars, said the filing further underscores that Trump’s own Twitter tirade against the judge who temporarily halted the ban has little basis in reality.

“The declaration by these ten former officials confirms what most of us already suspected to be true — that it’s just not the case that ‘many very bad dangerous people’ were ‘pouring into our country’ prior to the Executive Order,” Vladeck wrote in Just Security, “and that, if anything, it’s the Executive Order itself, and not preexisting immigration laws and policies, that poses a threat to our national security.”