There have been a lot of words written about whether or not President Trump can become a dictator in the mold of some radically diverse predecessors in the 20th century, from Hitler to Mussolini. Part of the issue with accurately predicting this is that Trump, with no previous political experience, gives us little to go on. But there are other issues with predicting the signs of an incoming dictatorship.
One is that authoritarian types of rule throughout the 20th century weren't all in the same mould, and that there's not a definitive one-size-fits-all recipe for fascism (tinpot dictators in Latin America and Haiti, for instance, differ significantly from the state-run machinery of Hitler's Third Reich). Another is that America is not a failed state, or currently in the grip of a severe economic crisis, or in possession of a strong tradition of authoritarian leaders, all of which are often breeding-grounds for dictatorships. It's all a bit tricky to predict.
Either way, part of being an informed citizen right now is to know the signs of dictatorship when they start to bleed into your country, even if you don't think that's particularly likely, or believe that Trump's dangers will be confined to (perfectly legal) guttings of the ACA, LGBT protections and other horrors. An unfettered weird white nationalist Tweeter with p*ssy-grabbing hands is bad enough; let's be vigilant about signals he might become even worse than that.
Assertions Of An Alternate Reality Via The Press & Propaganda
The reality of life under a dictatorship (under Kim Jong Un, for instance) is often a highly regulated and tailored experience. Dictators of all stripes seek to control information and how it's spun; they aim, according to Ron Fridell in Dictatorship, to "transform their citizens' thoughts and opinions and reshape expectations," via control of media and public discourse. They create a "fictitious world" that runs parallel to the real one, and demand that everybody believe in it and its tenets unquestioningly. Contradictory views aren't just denied, they're not actually allowed, and punishment for expressing disbelief or dissent can be severe.
Silencing & Discrediting All Opposition
The essence of dictatorship is that it can't actually be effectively challenged, because the legs of any opposition party or force have been metaphorically cut off. Arrests, ordinances forbidding public gatherings for any reason, violent suppression, interference with the work of opposition politicians and voices, and removal of the means and ability to create an effective opposition are all part of the beginner dictator's arsenal.
Part of this is the idea that any dissent or annoyed critique isn't actually a valid part of government, but "divisiveness" that need to be punished. Shalini Saxena, in Dictatorship, Fascism, and Totalitarianism, points out that this often extends not only to political opponents but to cultural ones, including artists, academics, and advocates of liberalism, and multiculturalism.
Disabling Public Accountability
2/ Public opinion rules in a republic & a free press is how the public stays informed. A free press is a vehicle of political accountability— Joanne Freeman (@jbf1755) January 23, 2017
Stephen Malt, writing for Foreign Policy about the signals of an incoming dictatorship and whether America needs to fear them, notes that "public accountability is inherent to America’s constitutional system, but that doesn’t mean Trump won’t try to escape it," citing systems in Russia, Turkey, and elsewhere in which the figures at the top of government remain untouched by reprisal or accusations of wrong-doing through tight control of legislature and the public. There are many mechanisms by which governmental figures are meant to be kept accountable (laws about nepotism or cronyism and bodies responsible for monitoring their behavior are examples). Their erosion, or a decision to completely ignore them, is a signal of poor respect for democratic processes.
Utilizing Nationalistic Rhetoric To Control Military Force
The place of the army is often a strong part of fascist rises to power, whether it's through military coups or other means. The unquestioning support of the military when putting schemes into practise is a pretty invaluable tool, one that Zachary Karbell over at Politico questioned in June 2016 could ever be truly afforded to Trump. Why? Because of the labyrinthine nature of codes about military obedience to the president when he's trying to do something illegal. What's more important when it comes to force, according to a compilation of political science on the subject by Professor Jeff Colgan, is the build-up of internal security forces, like the FBI. Surveillance and use of force or discouragement against one's own citizens, particularly dissenting ones, essentially requires a lot of spies.
Manufacturing Crises To Use Emergency Powers
One of the interesting things about dictatorships throughout history (and a good sign for people currently observing the U.S.) is that they often emerge out of political, economic and nationalistic crises. As Senior Fellow at the Cato Institute Jim Powell explained, Hitler rode to power on the back of a crushed Germany following World War I. That sort of volatile environment makes one of a dictator's top tricks, creating or fanning problems so that they can institute "emergency powers" and effectively take complete control without using the rule of law, pretty easy. It's well-known (and now a normal feature of movies) that they'll institute these crises themselves to get the right to declare martial law or extraordinary circumstances or whatever else they want.
Widespread Domestic Surveillance & Informers
Extremely rigid systems of governmental power don't work without intense regulation of the ordinary population. To whit, the beefing up of internal security in dictatorial situations is all about getting information, and using it to control people. Vast networks of informers are common (the Stasi was excellent at it), with encouragements for informing on basically everybody, and the consciousness that anybody around you might be sharing titbits to save their own skins. As The Nation reported in 2013, American governments have a long and depressing history of surveilling (and using agent provocateurs to demonize) resistance movements; but that's small potatoes compared to dictatorial practice, in which everybody is watched and private spaces become fraught with danger.
Abolishing Or Restructuring Checks & Balances To Power
There are a lot of institutions, in functioning democracies, to prevent heads of state getting everything they want all the time from everybody without consent or democratic agreement. The judiciary is one, and term limits and fair elections are another. (Megan McArdle, writing for the Chicago Tribune, emphasizes that those structures are very strong in America, though FDR had a history of playing fast and loose with them when he wanted something done.) Dictatorial heads of state will begin to interfere with these institutions and their ability to regulate, from stopping them performing their jobs to filling them with yes-men to ceasing their funding to abolishing them altogether.