“The effect of liberty to individuals is that they may do what they please; we ought to see what it will please them to do, before we risk congratulations.”

— Edmund Burke

As the unthinkable becomes likely, the question arises: Who is really to blame for Donald Trump?

The proximate answer is a durable plurality in the Republican primary electorate, concentrated among non-college-educated whites but not limited to them. They are applying Trump like a wrecking ball against the old political order. And it clearly does not matter to them if their instrument is qualified, honest, stable, knowledgeable, ethical, consistent or honorable.

At the CNN debate in Miami, GOP candidates sparred over immigration, social security, how to talk about Muslims and more. Here are the key moments. (Sarah Parnass/The Washington Post)

But why has this group of voters cohered, while other elements of the Republican coalition have fractured?

Some blame compromised Republican leaders who have resolutely refused to do things — such as unilaterally overturning Obamacare — that they actually lack the constitutional power to do. Or maybe the establishment invited a backlash for insufficient toughness on illegal immigration — though it is hard to imagine why public urgency would spike just as the flow of illegal immigration has slowed to a trickle. Or maybe a parallel establishment of conservative talk radio, PACs and websites gains listeners, funds and clicks by inciting conservatives against Republicans.

[Get ready, Donald Trump: You’re about to run into a buzz saw]

Or maybe, as reform conservatives have argued, Republicans have not adequately responded to 25 years of economic dislocation and wage stagnation — challenges faced by blue-collar families that simply don’t yield to a circa-1981 GOP agenda of tax cuts and deregulation.

The problem? All these same arguments were being made by the same people before Trump arrived on the scene. A new and unexpected development in U.S. politics has managed to confirm everything people already believed, suggesting that not much learning is taking place.

Whoever else might be implicated, it is necessary to say that Trump is to blame for Trump. The fact that he is appealing to understandable concerns does not make him a valid or responsible voice. In the aftermath of the 9/11 attacks, for example, President George W. Bush could have chosen to blame Islam and stir up prejudice. He didn’t. In the aftermath of the Paris and San Bernardino, Calif., attacks, Trump did, picking on a religious minority for self-serving political reasons.

In a dangerous world, fear is natural. Cynically exploiting fear is an art. And Trump is a Rembrandt of demagoguery.

But this does not release citizens from all responsibility. The theory that voters, like customers, are always right has little to do with the American form of government. The founders had little patience for “pure democracy,” which they found particularly vulnerable to demagogues. “Men of factious tempers, of local prejudices, or of sinister designs,” says Federalist 10, “may, by intrigue, by corruption, or by other means, first obtain the suffrages, and then betray the interests, of the people.” A representative government is designed to frustrate sinister majorities (or committed pluralities), by mediating public views through “a chosen body of citizens, whose wisdom may best discern the true interest of their country.”

[Charles Krauthammer: Donald Trump, defender of the Faith]

Trump is the guy your Founding Fathers warned you about. “The question is not ‘Why Trump now?’ ” argues constitutional scholar Matthew J. Franck, “but rather ‘Why not a Trump before now?’ Perhaps some residual self-respect on the part of primary voters has driven them, up to now, to seek experience, knowledge of public policy, character, and responsibility in their candidates. The Trump phenomenon suggests that in a significant proportion of the (nominally) Republican electorate, this self-respect has decayed considerably.”

With the theory of a presidential nominee as a wrecking ball, we have reached the culmination of the founders’ fears: Democracy is producing a genuine threat to the American form of self-government. Trump imagines leadership as pure act, freed from reflection and restraint. He has expressed disdain for religious and ethnic minorities. He has proposed restrictions on press freedom and threatened political enemies with retribution. He offers himself as the embodiment of the national will, driven by an intuitive vision of greatness. None of this is hidden.

The founders may not have imagined political parties as a check on public passions, but that is the role the GOP must now play — as important as any in its long history. It is late, but not too late. If he loses in Ohio and Florida on March 15, Trump may well be held below a majority of delegates at the Cleveland convention. And then this chosen body of citizens should play its perfectly legitimate role and give its nomination to a constructive and responsible leader.

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