Parliamentary democracy is often tumultuous, but like a slippery fault system, the turmoil tends to release pent-up tension gradually, in regular small bursts, rather than catastrophically, all of a sudden. To become prime minister, a politician needs to climb the ranks through the system— a process that tends to weed out reactionaries and radicals. To remain in power, a prime minister needs to nurture the respect of the coalition that promoted her or him in the first place. Should the parliament lose confidence in the prime minister, it selects another, or parliament is dissolved and the country holds a general election.
Presidential systems impose no similarly moderating influences on ambitious demagogues. Linz recognized that by forcing two different, popularly elected branches of government to share power—like twin princes fighting for the throne—presidential systems give rise to legitimation crises almost by design. A few years before Linz died, this observation was borne out dramatically by the consecutive U.S. elections of 2008 and 2010, when voters installed a Democratic president by a landslide, then a Republican House of Representatives by another landslide. The question of which branch of the government was the more legitimate voice of the people pitted Congress and the White House against each other in dangerous brinkmanship. Within months of the 2010 midterms, the government nearly ceased functioning twice, the second time amid a threat by the GOP majority to undermine the supposedly inviolable validity of U.S. debt.
That crisis, which courted global economic calamity, was resolved at the last minute when President Obama largely acceded to House Speaker John Boehner’s demands. But the episode raised an alarming question: What happens when we have a president who refuses to be so accommodating?
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It is no great stretch to interpret Trump’s rise as a phenomenon driven by disgruntled masses abandoning democracy in favor of autocracy—as part of the natural progression of Linzian decay. But it’s also possible that American democracy really is unusually resistant to systemic breakdown and can endure even the unprecedented challenges that Trump could pose. Maybe, despite the potential for crisis that’s baked into our way of governing, we can relieve these systemic tensions in other ways: through party realignments, through sheer institutional robustness, or through popular insistence that we uphold our constitutional traditions. In that more optimistic light, Trump looks less like doom for the republic than doom for the Republican Party.
If Trump were to govern with a more even keel than he’s led us to expect, his presidency could conceivably serve as a weird remedy to the constitutional problems we’re already experiencing—and end up being powerful evidence of the political anti-gravity that keeps our democracy from succumbing to ideological polarization.