Trump's favorite tactic: criminalizing his critics

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Julian Zelizer is a history and public affairs professor at Princeton University and the editor of "The Presidency of Barack Obama: A First Historical Assessment." He's also the co-host of the "Politics & Polls" podcast. Follow him on Twitter: @julianzelizer. The opinions expressed in this commentary are his own.

(CNN)This past week President Donald Trump went after some of his favorite targets. Within the span of a few days, he lashed out at migrants in Central America who are seeking legal asylum in the US, dismissed his predecessor as "Cheatin' Obama," brought back his false claims about voters committing massive fraud in the 2016 election and went after a few of his most-hated news organizations, including CNN and the Washington Post. "The Washington Post is far more fiction than fact," the president tweeted Sunday morning.

None of this is new. The rhetorical barrage of anger is a prime example of the president's favorite political tactic -- he classic wartime strategy of vilifying, criminalizing and dehumanizing the "enemy."
In times of war, it has been common for presidents to drum up public support for a military operation by rallying the nation against an evil that lurked overseas. Sometimes it hasn't taken much effort by a president to make this case, such as with Adolf Hitler in the early 1940s. Other times, such as with Saddam Hussein in 2002 and 2003, the commander in chief faces a much bigger challenge in trying to prove that an enemy represents a direct threat that requires military action.
This tactic has been central to the President's method of political combat at home. Often using catchy monikers to make his case, President Trump goes all in when he rips apart a target, with the goal of making certain the public can never look at that person or institution the same way again. By the time he is done with them, Trump's hope is that the public won't trust an individual or organization, won't believe anything that they say and will fear them as threats to the republic.
    Since showing that he could do this to his Republican primary competitors and then Hillary Clinton, Trump has stuck to this playbook. His vitriol has been intense and he has been willing to go to extreme lengths -- stretching the truth or making things up -- to generate fear and anger.
    Take the legal and unauthorized immigrants who have constantly been in his crossfire. Rather than focusing on simply selling a hardline policy toward our borders, the president has set out to spread fear about the problems he says undocumented immigrants bring to the nation.
    Although he occasionally acknowledges the important contributions of immigration to our economy and society, Trump is much more interested in talking about the darker side. From describing incoming Mexicans as rapists and criminals to constantly warning of the threat of MS-13 to our suburbs to falsely charging that immigrants behind some kind of massive voting fraud to claiming that "American" jobs are being stolen, Trump has tried to turn those coming into our country into a devious invading force that undermines our security and safety.
    Rather than pushing back against news stories that are critical of his administration, the president has gone all-out in attacking almost the entire news media, outside of Fox News and Sinclair Broadcasting, as being totally illegitimate. In his rhetoric, the news industry can't be trusted. He claims they spread false information and hire people who are consumed with bringing down his presidency.
    The term "fake news" has now become a permanent part of the political lexicon. He has targeted several individual leaders of news organizations to try to make them villains in the public mind, perceived as carrying out a grand conspiracy against his White House.
    The FBI and the intelligence agencies are not only wrong in their assessments of Russian meddling in the 2016 election, according to President Trump, but they are run by evil actors who want to take him down.
    He has vilified specific agents and agency leaders, such as James Comey and Andrew McCabe, as being partisan hacks using the tools of law enforcement to promote false information. He has used the emails between agents as evidence that the agencies are making decisions based on politics. And now he is going after special counsel Robert Mueller and his team in a similar way.
    While this kind of overblown rhetoric is common in foreign policy and can cause immense harm, the consequences are extraordinarily damaging when it comes to domestic policy. Most important, the social groups and organizations that are the target of his ire will suffer long-term effects. Because the blasts are coming from the president of the United States, someone who commands passionate support from broad swaths of the electorate, his accusations will stick in the minds of many voters.
    The attacks will outlast his presidency. Dangerous social biases against groups like immigrants will shape how parts of the electorate approach law, politics and their own communities. Law enforcement operations will be seen as illegitimate even when they are desperately needed. Many Americans will automatically disbelieve high-quality journalism.
    This kind of warlike mentality also makes political compromise that much more difficult. Given the intense partisan polarization that we already face, this is the last thing that our Republic needs. At some point, when one half of the public sees the other as criminals or villains, negotiation becomes impossible.
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    It becomes more difficult to reach any sort of common ground, and the will to enter into discussions disappears. The level of trust the other side will have for the GOP, moreover, vastly diminishes after being on the receiving end of this bombardment. A president who loves to polarize and divide will amplify the deep divisions that already have taken root in our political system.
    The attempted criminalization and dehumanization of his opponents is one of the most distinct elements of Trump's political style and could be one of the most lasting consequences of his presidency. The targets he leaves behind won't be able to recover quickly from the damage he has inflicted. And America's road to recovery from extreme polarization will be more remote than ever before.