Steve Schmidt, the veteran GOP strategist who worked in the George W. Bush White House and ran John McCain’s campaign for president, accused Republicans of complicity with the “vile” Trump administration and its “evil” policies unless they follow him and quit the party.

Schmidt announced Tuesday night that he had formally left the party over Trump’s policy of separating families at the U.S. border with Mexico.

Speaking to The Daily Beast, he called for his old boss, President Bush, to set aside political convention and come out to publicly challenge Trump’s grip on both the country and the Republican Party, which he feels is set to collapse. “This is a metastasis, a cancer, a toxin that has destroyed the Republican Party,” he said.

He said he fears that “cowards” Paul Ryan and Mitch McConnell have failed in their constitutional duty to act as counterweights to the Executive Branch, opening up the possibility that an era of liberal American democracy could be coming to an end.

“The American people are fed a daily diet of nonsense-talk and lies in the form of what is effectively state media on Fox News and nobody should underestimate the threat posed by a political party where conservatism is now defined by absolute obedience to a leader with autocratic tendencies who fetishizes dictators and autocrats all over the world,” he said.

“Trump didn’t destroy the Republican Party—it’s the cowardice of the Republican leaders, their complicity in all of it, the lack of courage to stand up for what's right.

“Republican members of Congress are cowed and fearful of Trump and they have abrogated their oaths to defend the Constitution of the United States from Trump's attacks on the rule of law; on objective truth; his defilement of important institutions; his sundering of the American people; his betrayals of the Atlantic alliance; his racism; and his cruelty. The party has become profoundly corrupt, both financially in the form of men like Scott Pruitt and Jared [Kushner] and Ivanka [Trump], but also intellectually rotten and corrupt.”

Schmidt, who was campaign manager for Arnold Schwarzenegger’s re-election as governor of California, said he believes that the Republican Party has been so badly damaged by the Trump presidency that it will not be able to recover.

He fears the party’s virtual annihilation in California, where registration rolls now show fewer Republicans than unaffiliated voters and many races are fought between two Democrats, is a foreboding warning for it nationwide.

“Whether they’re for good or bad, all trends in the United States start in California,” Schmidt said. “When you look at the demographics of the Republican Party today, its embrace of white ethno-nationalism; blood-and-soil politics of the type that you traditionally see in the European far-right—the Republican Party demographically will face its demise.”

Schmidt said he mourns the “heartbreaking” transformation of the Republican Party, not because he believes that the push and pull of a center-left and center-right party is beneficial for any democracy, but he says he has always had respect for both of America’s great political parties.

“A mark of stupidity is a belief that one party is totally virtuous and correct on the issues while the other is evil and always wrong. The truth of the matter is that both of these political parties have been essential institutions not just in the country but in the history of the world,” he said. “They have both produced good leaders and bad leaders. But neither has ever produced a leader as profoundly dangerous to the notion of small ‘l’ liberalism, of democracy, of freedom as it has in Donald Trump.”

For Schmidt, the Trump administration’s policy of forced separation of families was the final straw for his own membership of the party, he said he would now support the Democrats.

“Make no mistake about it when you're ripping breastfeeding children away from their mothers and putting them in detention facilities. That's an evil policy,” he said. “To see the Republican Party break up the way it has to lose its moral compass it is tragic, it's tragic for me personally, but I won't be part of it. I won’t share a party label with people who think it’s all right to put babies in internment camps. My fidelity is to my country, not my political party. Country first.”

The failure of the Republican leadership to challenge the policy has also left him appalled. “You literally have nobody who’s willing to fight and to stand up to recognize the extraordinary moment in time, none of the elected official class. And so we have a spectacle in the United States where there are internment camps along the southern border. A policy that is morally reprehensible that speaks to the worst moral outrages in the history of the country; the separation of families at the auction blocks during slavery; the separation of children from Indian families.”

As set out in the Constitution, Congress is supposed to temper the power of the White House. “Could American democracy roll back? Could you have an autocratic leader? Can you have a president who asserts that his power is unchecked—and it is unchecked? The system of government in the United States as designed by the Founders always anticipated that one day there would be a President Donald Trump. What it didn’t anticipate was the abdication of duty by the co-equal branch of government to check the Donald Trump and that would be the United States Congress,” he said, singling out Ryan and McConnell’s utter failure to challenge Trump.

“They’re the heads of a co-equal branch of government. They have powerful offices and positions and they could have checked him. They could have set guardrails and boundaries. They could have stood up for what's right. Both of them are cowards.”

In the absence of constitutional checks, Schmidt says Americans reluctantly must cast their eyes toward Europe in the 1930s.

“What are the hallmarks here? He uses mass rallies to incite fervor and followers who are now more like cult members than voters,” he said. “Every problem has an easy group to blame—minorities, chiefly—he creates a sense of mass victimization, he alleges conspiracy by unseen forces, and he asserts that only he can stop it and protect the victims—and stop the villains, the minorities. The last step of this is an assertion: ‘I'll just need more powers to do it.’ And that's how a constitutional republic dies.”

In the absence of leadership on Capitol Hill, Schmidt says it may be necessary to hear from leaders of the past.

“Both George W. Bush and Barack Obama are good men,” he said. “The question the former presidents have to ask: Is there a moment in time that they are compelled to speak, and compelled to speak together? These men are addressed by that title ‘Mr. President,’ which is the highest that can be bestowed in American life. And I do think an hour is approaching where we have a crisis of leadership. With the fragility and the importance of our democratic institutions at stake, it would be nice to hear from them.”

“We have in America—right now, at this hour—to understand that you have a lawless president, a vile president, a corrupt president, a mean, cruel president, who is seeking to remake the world order.”