Others prefer to blame immigration, political correctness or simply the overweening arrogance of America's self-appointed mandarin class.
Proponents of these explanations can point to compelling evidence. But that evidence conceals the same fatal flaw in each story: the attempt to explain a novel phenomenon by way of some long-term factor that hasn't changed, or else to explain a global phenomenon in terms of some local peeve.
American racism, for example, is the left's favorite explanation for the rise of Trump. Columbia University sociologist Musa Al-Gharbi has pointed out a number of flaws in this thesis, the most glaring of which is that the United States has been racist for a long time and much more racist in the past than now -- but now is when America elected Trump.
You might argue that it took a novel event to fan the embers of the nation's latent racism -- something like, say, the presidency of Barack Obama.
But that argument only briefly satisfies, because Trumpish leaders seem increasingly popular throughout the world. Rodrigo Duterte in the Philippines, Jair Bolsonaro in Brazil, Viktor Orban in Hungary -- it's hard to argue that all those voters, of different races, languages and cultures, were identically unnerved by the sight of Obama in the Oval Office.
In fact, it's hard to argue that any flavor of American identity politics can explain what has become a global phenomenon: the collapse of the formerly liberal left into two wings, one increasingly socialist, the other increasingly identity-focused; and the displacement of the formerly liberal right by unapologetically nativist, protectionist and populist upstarts.
Trying to detect a hidden order behind the rise of Trumpish figures around the world might be as pointless as a child's search for faces in the clouds. But there's a good chance that they really are linked. To find out how that happened will require letting go of local grievances and starting to look for the global thread that ties together such distant, disparate characters.
The most obvious candidate is the global financial crisis of 2008, which was certainly widespread, and offers eerie parallels with 1930s Europe. But that explanation doesn't quite work, because the crisis wasn't the same everywhere -- World Bank statistics on per-capita gross domestic product show that Brazil and the Philippines were relatively unscathed.
Perhaps the most compelling answer is that the internet, and particularly social media, is disrupting politics the way it has disrupted everything else -- nearly everywhere, and all at once. No, I'm not talking about Russians buying Facebook ads. I'm talking about something much deeper and more pervasive.
It's striking that two of the 20th century's periods of greatest political upheaval followed the arrival of a revolutionary communications technology -- the 1930s were preceded by the spread of radio, the 1960s by the arrival of television. Both mediums fundamentally changed people's relationship with information, and in the process, radio and television necessarily altered politics.
Many of the explanations for what's going on in politics ultimately describe a product of this sort of technological change. Take mass immigration. By making it easier to stay in touch with family back home, the internet and cellphones have dramatically lowered the emotional cost of migration. They've also made it easy to disseminate successful strategies for evading border controls or to recruit new migrants, as the recent migrant caravan from Central America reportedly did, on Facebook and WhatsApp.
The internet also let candidates such as Trump rail against those migrants. He has no trouble finding a platform now, but it's hard to see how he could have gotten there without social media to turn him into a one-man broadcasting station. One can't really imagine him writing a serious book such as Barry Goldwater's "The Conscience of a Conservative"; devoting a substantial portion of his own fortune to a political campaign, a la Ross Perot; or spending patient decades building up a grass-roots organization, as Ronald Reagan did.
The nice thing about this theory of the internet's influence in politics is that it offers a global explanation. What's less nice is that it probably means more convulsions until societies have fully processed the technological shift: 2019 is apt to look like 2018, only more so.
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