Mike Segar / Reuters

On Tuesday night, Donald Trump Jr. cleared the low bar set by his stepmother: If his speech were a term paper, he wouldn’t have been expelled. But he managed to spark a minor controversy nonetheless. Some of his best lines appeared to be copied from articles by the conservative writer F.H. Buckley.

In the end, it turned out Buckley himself was the one who did the copying. He helped write the speech. The moment the story broke, he took to Twitter to explain. “It wasn’t stealing,” he said.

Fair enough. But it was definitely something. Since leaving the White House six months ago, I’ve published a few articles. I’ve also been paid to write a few speeches. It never would have occurred to me to copy from column A and paste into column B. It’s simply not done. The former Carter speechwriter and Atlantic national correspondent James Fallows said the same thing. So did my former Obama White House colleague Jon Lovett. I know plenty of freelance speechwriters. I have yet to hear one say that borrowing from one’s own columns is par for the course. This decision was not nearly as bad as Melania’s. This was not outright plagiarism. But it came close to, and possibly crossed, an ethical line.

Trump Jr.’s defenders insist they have nothing to defend. They point out that any politician who hires a speechwriter uses another person’s words. They’re right, in a sense. Ghostwriting is a gray area, held to standards somewhere between the strict ones of journalism and the practically non-existent ones of, say, dinner party chat. But that’s precisely the point. With no official code of conduct, or threat of being disbarred,  speechwriters are governed by norms rather than bylaws. One of those norms is that writers try to come up with original ideas. If a writer has a really juicy line about the middle class, she can publish it under her own name for less money, or put in a speech for more money. Not both.

I’m not suggesting that America pity the professional speechwriter. We’re doing fine. And if this were the only unwritten rule already broken in Cleveland, it wouldn’t be worth writing about. But it’s not. Until this week, people at party conventions didn’t pander to white supremacists. They didn’t call for the other party’s nominee to be thrown in prison. If a campaign is caught plagiarizing the sitting First Lady—to use a hypothetical example—they don't chalk it up to coincidence, or quote My Little Pony as a defense. Donald Trump Jr.’s speech isn’t another example of outright fraud. It’s another small example of what happens when cutting corners in pursuit of power becomes a way of life.

And it's a clear red flag. As has been pointed out many times in the last two days, leading a campaign is not nearly as hard as leading a country. The real concern is not what Donald Trump, Jr. said as a keynote speaker. It’s what his dad would do as president. Commanders in chief  have extraordinary amounts of power, often checked only by self-restraint: to pardon criminals, to bomb countries, to call out the National Guard. Even the U.S. Constitution’s checks and balances are rooted in an unwritten rule: Presidents don’t disregard rulings from the Supreme Court.

Neither of the Donald Trumps seem to care about these rules. Perhaps they don’t even realize the rules exist. That’s why Donald Jr.’s speech matters. It’s not a full-blown scandal. It’s not even the most controversial thing said last night. But it’s a rhetorical warning sign.

This is what the erosion of democracy looks like. Sooner or later, Americans will have to stand up not just for the laws that govern us, but the norms that protect us. As F.H. Buckley once put it, "More essential to freedom than rights or laws is something like chivalry." Words to live by—and perhaps even to copy and paste.

We want to hear what you think about this article. Submit a letter to the editor or write to letters@theatlantic.com.