Will 2016 bring out the Democratic Party's worst instincts when it comes to economics and class?

On the left, Hillary Clinton is basically mathematically guaranteed to be the Democratic presidential nominee. And with the departure of Ted Cruz and John Kasich from the race, trade protectionist Donald Trump has officially sewn up the GOP nomination.

To understand the potential problem this match-up creates for the Democratic Party, you have to start with its coalition. In demographic terms, it's a mishmash of upper-class whites, women, African-Americans, Latinos, and the young — the famous Obama coalition. But in class terms it's an odd partnering of two opposite ends of the income spectrum: college-educated professionals on one end, and on the other, basically everyone in the poor and working class who isn't a straight white religious male.

Needless to say, with its outsized social, economic, and political power, it's the college-educated professional class that sets the tone and agenda for the Democratic Party. As Thomas Frank recently noted to PBS, this creates a kind of tunnel vision.

The Democratic ruling class is not nearly as liberal on economics as the rest of the Obama coalition — what it really has in common with them is its stances on social issues and identity politics. That is the virtuous self-conception around which the college-educated professionals of the Democratic Party have organized themselves: They see themselves as diverse, cosmopolitan, enlightened, meritocratic, upwardly striving, and intellectually sophisticated.

It's just impossible to overstate what a perfect foil Trump and his supporters are for this worldview.

Trumpism appears vulgar, jingoistic, bigoted, instinctively violent, and incipiently fascist. Its supporters are much more likely to be less educated. The temptation for upper-class Democrats to view 2016 as a clash between civilization and the barbarian hordes is going to be overwhelming. Indeed, liberal commentators are already succumbing.

So we could be in for a campaign of moralistic chest-thumping from the Democrats, correct on many of its ethical merits but insufferably elitist all the same — a campaign that equates the values and worldview of the college-educated upper-class with right-thinking and moral goodness.

But the deeper problem will be the Democrats' temptation on the policy front. Because the simple fact is, Trump's supporters have legitimate grievances. They've been left behind and exploited by the economic changes of the last few decades, whose benefits have gone overwhelmingly to the upper class. And because many of them are neither exactly poor nor exactly upper class, they've stumbled into a political no man's land: Their actual economic needs have been ignored by both the GOP's party establishment and donor class and by the Democrats' platform — they fit nowhere in the latter's coalition, and helping them would require far more spending on public investment and expansions of social insurance than the Democrats are currently willing to contemplate.

Trump has never been a conservative ideologue, and has shown himself willing to answer to the incipient if muddled economic liberalism of his supporters. Just this week, he backtracked from his own tax plan, basically a massive tax relief for the wealthy. He questioned his previous opposition to minimum wage hikes, saying it was something he'd look at. And he made positive noises on debt spending and low-interest rates, pitching the GOP's deficit and inflation hawkery over the side. Like the populist-left Sanders, Trump ferociously opposes the Trans-Pacific Partnership (TPP), and is hostile to free-trade deals in general. And he's said nice things about universal health care, and has promised to preserve Social Security and Medicare from cuts.

If Trump continues tacking towards the economic center, how will Clinton react to distinguish herself? Especially if she's trying to please both her party's urban professional vote, while trying to woo anti-Trump Republican voters at the same time? At best, she may try to reassemble the Obama coalition around social liberalism and social and identity politics and simply ignore economics. At worst, she may rethink her own support for a $12 minimum wage and her own newfound opposition to the TPP, and maybe even consider a grand bargain to cut Social Security and Medicare. In so doing, Clinton would solidify the notion that social liberalism is naturally paired with a slim-downed welfare state, free markets, and budget hawkery — a perfect storm of elite anxieties that the unwashed masses are culturally backwards and economically illiterate.

This would be an unmitigated moral disaster for American politics.

I don't want to downplay the fact that Trump's rise really does herald something unusually frightening and morally reprehensible in American politics. But the continued obsessive focus on this one point by liberals and Democrats is beginning to look less like clarity of analysis, and more like sclerosis and vanity.

The question before them now is what to do about it: Will Clinton and the Democrats choose to quarantine Trumpism with a coalition built around elite abhorrence? Or will they choose to deflate Trumpism by engaging head-on with its legitimate grievances and going hard to Trump's left on economics?

The general election has barely begun, so Clinton and her party could still go with the second option. But I'm not optimistic.