Mussolini’s testing of Italians through violence showed the weakness of the ruling political establishment. A blend of fear, opportunism, and desire to defeat Italy’s powerful left led many liberals to support Mussolini. Most disliked him but thought he could be mainstreamed or placated once given some power. After he became prime minister, the violence did not abate. Yet key liberal voices such as the philosopher Benedetto Croce and former Prime Minister Antonio Salandra continued to endorse him.

Finally, the Fascists went too far. In June 1924, they assassinated the popular Socialist politician Giacomo Matteotti for accusing them of electoral fraud. Mussolini, denounced by the opposition press as responsible, faced the biggest crisis of his political life. By December, many liberal holdouts had turned against him.

They had waited too long to withdraw their support. On January 3, 1925, Mussolini announced the end of democracy in Italy. “I alone assume political, moral, and historical responsibility for all that has happened.” Mussolini told Parliament. “If Fascism has been a criminal association, then I am the chief of that criminal association...”

Violent language and acts had defined Fascism since its inception. Yet this shocking speech ruined the comforting fable many Italians told themselves: that Mussolini was a sheep in wolf’s clothing, and he would embrace reform rather than revolution once in power. After January 3 and the spate of repression that followed, it was difficult to disassociate the statesman from the squadrist, as Italian elites had tried for years to do.

For over a year now, Trump has been subjecting Americans and American democracy to analogous tests. Actions many see as irrational make chilling sense when considered under this framework: the many racist tweets or retweets, which his campaign then declares a mistake. His early declaration that he could shoot someone on Fifth Avenue in New York and not lose any supporters. His extended humiliation of powerful politicians such as Paul Ryan and John McCain. His attempt to cast doubt on the legitimacy of the American electoral process. His intimation that “the Second-Amendment people” might be able to solve the potential problem of Hillary Clinton appointing judges, presumably by shooting her. This last remark is a sign that Trump feels emboldened in his quest to see how much Americans and the GOP will let him get away with—and when, if ever, they will say “enough.”

Authoritarians usually communicate their intentions clearly. Mussolini certainly did. Trump has been frank about his agenda and the groups he’ll target if he’s elected. “The crime and violence that today afflicts our nation will soon come to an end. Beginning on January 20, 2017, safety will be restored,” Trump said in accepting the Republican presidential nomination. It’s not necessary to label Trump a Fascist to discern the dangers of such rhetoric. There’s no need to see a trajectory to dictatorship to recognize that Trump is testing American decency and the strength of U.S. democracy. The history of Mussolini’s rise coincides with the fall of what had been Italy’s version of a Grand Old Party: the liberal factions that had ruled Italy from Unification onward. They never recovered from their acquiescence to the Duce. Of the many lessons the GOP can take from its experience with Trump so far, this might be the most valuable.

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