Both sides in American politics tend to believe that their opponents are less principled and more ruthless than they themselves are, willing to do anything in furtherance of their nefarious goals. We might disagree about which side is right on that score, but there's no doubt about who's more effective in the strategic deployment of a critical political tool: outrage. Republicans have honed it to a fine art, and there's no better evidence than the fear right-wing outrage inspires in Democrats, the media, and even Republicans themselves.

If you think all that shouting at the cameras and into talk-radio microphones is just sound and fury, let me refer you to this inside account in The Washington Post of the decision-making that led to FBI Director James Comey sending congressional Republicans a letter, nine days before the election, informing them that the FBI had some of Hillary Clinton's emails it was going to look at. Comey's letter — which, it has become increasingly clear, put Donald Trump in the White House — was the product of fear, specifically fear of the conservative outrage machine. And the one person who could have stopped him, Attorney General Loretta Lynch, stood down and let it happen, for exactly the same reason.

Comey's letter was not only unprecedented, it was a clear violation of FBI policy, which states not only that the bureau should not comment publicly on pending investigations, but that they need to be particularly careful not to discuss investigations about any public official in the days before an election, since that could sway the results. But despite the fact that he didn't even know what was in the emails, let alone whether there was any reason to suspect something criminal might emerge (and as it turned out, there wasn't), Comey decided to violate that policy, and do so in a way that would reinforce exactly the argument Donald Trump was making about Clinton.

A greater gift Trump could not have dreamed of. Just as anyone who had been paying attention would have predicted, the news media seized on Comey's letter as though it were a combination of D-Day, the moon landing, and the death of Michael Jackson.

So why did Comey do it? "Battered by Republican lawmakers during a hearing that summer, Comey feared he would come under further attack if word leaked about the Clinton case picking up again." He was afraid of the Republican outrage machine. What would they accuse him of? What names would they call him? What vitriol would he have to endure? Whatever he imagined, the thought was too much to bear.

And Loretta Lynch, who is Comey's boss, could have ordered him to adhere to departmental policy and refrain from injecting himself into the presidential campaign in such an inflammatory way. But she didn't. Why? "Lynch and her advisers were nervous about how it would look if people found out that she, a Democratic presidential appointee, told Comey to keep secret from Congress a new development in the Clinton investigation." In other words, she too feared the outrage machine. And the result was that Donald Trump will be president of the United States.

Some might protest that Democrats try to gin up outrage, too. Which is true — they're just not nearly as good at it. Republicans have a combination of resources and focus that Democrats just can't match. They have talk radio — an entire medium built on outrage — where liberals have an anemic presence. They have Fox News, a network that creates, channels, and maintains conservative anger. And they have members of Congress always eager to use their official capacity to feed the outrage machine.

Try to imagine something like Benghazi happening during a Republican administration with a Democratic Congress. Would Democrats have had the single-mindedness to undertake not one, not two, but eight separate congressional investigations of it, long after everyone understood that though the events were tragic, there was no official malfeasance? Not on your life. And when Republicans give them cause for outrage, with cases like their refusal to allow President Obama to fill a vacant Supreme Court seat, Democrats express their disapproval, complain that norms are being violated, and then pretty soon move on to other things.

Or think about what happened when Barack Obama took office in 2009. The immediate result was an entire movement, the Tea Party, devoted to outrage. Through a combination of grassroots mobilization and elite direction, it seized the agenda, enforced ideological rigidity, promoted voter turnout, and terrorized Republican lawmakers. Then it got Donald Trump nominated for president, in large part because the other Republican candidates just couldn't channel the GOP base's anger in quite so colorful a way.

Much of the time, all that outrage is just background noise to our politics. It's your father-in-law watching Bill O'Reilly and complaining about kids today with their rap music who won't pull up their pants, it's a bunch of radio shows you don't listen to, it's backbench congressmen prattling on about battles they've already lost. But sometimes, as we saw with Comey and Lynch, the outrage machine can be brutally effective and change the course of history.

But that's never an inevitable outcome. If Comey or Lynch had been more courageous, they could have said, "Yes, I'll be shouted at if I do the right thing. But I'm going to do it anyway." The outrage machine works by creating fear — but it's up to everyone else whether they succumb to that fear or not.