And Mr. Ryan, after a brief pretense of agonizing about Mr. Trump, is now in full attack-dog mode on the candidate’s behalf. After all, the Trump tax plan would be a huge windfall for the wealthy, while Hillary Clinton would surely sustain President Obama’s significant tax hike on high incomes, and try to push it further.

I’m not saying that all leading Republicans are racists; most of them probably aren’t, although Mr. Trump probably is. It is that in pursuit of their economic — actually, class-interest — goals they were willing to act as enablers, to make their party a safe space for prejudice. And the result is a party base that is strikingly racist, in which a plurality of voters believe that Mr. Obama is a Muslim, and more — a base just waiting for a candidate willing to blurt out what the establishment conveyed by innuendo.

But there’s one more crucial element here: We wouldn’t have gotten to this point if so many people outside the G.O.P. — in particular, journalists and self-proclaimed centrists — hadn’t refused to acknowledge what was happening.

Political analysts who tried to talk about the G.O.P.’s transformation, like Norman Ornstein of the American Enterprise Institute, were effectively ostracized for years. Instead, the respectable, “balanced” thing was to pretend that the parties were symmetric, to turn a blind eye to the cynicism of the modern Republican project.

Which brings me back to Mr. Ryan, the de facto leader of his party until the Trumpocalypse. How did he reach that position? Not by inspiring deep loyalty in the base, but rather by getting incredibly favorable treatment from journalists and centrists eager to show their bipartisanship by finding a serious, honest Republican to praise — or at least someone able to do a passable job of playing that character on TV. And as the latest from Fix the Debt shows, the charade is still going on.

The point is that this kind of false balance does real harm. The Republican establishment directly enabled the forces that led to Trump; but many influential people outside the G.O.P. in effect enabled the enablers. And so here we are.