Clinton has the upper hand against a ludicrous opponent

Mr. Sargent summarizes the case very well, but let me do it a bit differently: Think about Mr. Trump’s obvious weaknesses, and why Republicans couldn’t exploit them but Democrats can.

First, he’s running a campaign fundamentally based on racism. But Republicans couldn’t call him out on that, because more or less veiled appeals to racial resentment have been key to the party’s success for decades. Mrs. Clinton, on the other hand, won the nomination thanks to overwhelming support from nonwhite voters, and she will have no trouble hitting hard on this issue.

Second, Mr. Trump is proposing wildly irresponsible policies that benefit the rich. But so were all the other Republican candidates, so they couldn’t attack him for that. Mrs. Clinton can.

Third, Mr. Trump’s personal record as a businessman is both antisocial and just plain dubious. Republicans, with their cult of the entrepreneur, couldn’t say anything about that. Again, Mrs. Clinton can.

The G.O.P.’s paralysis on these issues explains why, again and again, Republicans turned to a proven line of attack - that is, proven not to work - insisting that Mr. Trump isn’t a true conservative, which doesn’t matter to voters at all. Obviously, Democrats will be able to highlight different and, I imagine, much more salient issues.

And there’s one last thing, which I suspect may make the biggest difference of all: Mrs. Clinton’s campaign can go after Mr. Trump’s fundamental buffoonery.

He is a ludicrous figure, and the more we learn the more ludicrous he seems. So why couldn’t Republicans make that stick? I’d argue that it was because there was something fairly ludicrous about all of his Republican opponents, too.

Think about Marco Rubio: It was obvious that he was a prefabricated candidate - a nice-looking guy with no real convictions or experience, reciting lines he was told to deliver. The infamous line - “We must dispel with …” - wasn’t just vile and stupid (even the first time, let alone repeated), it was also, transparently, not something Mr. Rubio believed or even cared about. His handlers had simply told him to say it.

Or think about Ted Cruz, whose meanspiritedness and self-centered nature stand out even in today’s conservative movement, making him a hated figure among those who should like his message.

Mrs. Clinton, on the other hand, is not ludicrous. She can think on her feet and is tough as nails. Do you really think the person who stared down the Benghazi committee for 11 hours is going to wither under schoolboy taunts?

The news media will, I fear, try their best to pretend that the contrast isn’t what it is. We’ll hear endless explanations about why Mr. Trump’s vanity, ignorance and lack of moral fiber somehow prove his “authenticity,” which Mrs. Clinton somehow lacks. And maybe that will stick with voters. But I don’t think it will.