When the Watergate tapes were released, some Americans were dismayed at the many “expletives deleted” that Richard Nixon employed in private conversation. But as historian Stephen Ambrose pointed out, Nixon had insisted that even the milder words “hell” and “damn” be deleted from the transcriptions, creating the false impression that his language was saltier than it actually was. “If my mother ever heard me use words like that,” Nixon explained, “she would turn over in her grave.”

No inner check constrained Donald Trump from using the F-word during a presidential campaign rally in Portsmouth, N.H. “We’re gonna have businesses that used to be in New Hampshire, that are now in Mexico,” he told a crowd, “come back to New Hampshire, and you can tell them to go [bleep] themselves!”

Many people, particularly the ones unburdened by knowledge of economics, will respond, “Hell yeah!” We are a culture conditioned by cable television, which has made the language of sailors, mobsters and New York real estate developers available to any digitally literate 11-year-old. Even the cable channels you don’t pay for have taken to constant, blindingly obvious bleeping, in a wink and nod to their perception of modern usage. This, after all, is the way “real life” sounds.

Let us hope not. In real life, expletives are often used as a form of aggression or cruelty. A co-worker who tells you to Trump yourself is usually being unpleasant. A co-worker who does this every day is often creating a hostile or demeaning work environment. Language suitable for decent company is a form of politeness, which is a species of respect, which is an expression of morality. And if I am the last holdout on this issue, so be it. I don’t really give a damn.

Win or lose, Trump has brought the language and sensibilities of cable TV to presidential politics. This is a relatively small transgression in a campaign that has involved groundbreaking appeals to ethnic and religious resentment. But there is a rhetorical strategy at work here worth noting. In recent rallies, Trump — in addition to telling people to go “F---” themselves — said he would “beat the s---” out of anyone attacking us and has now charmingly (and by “charmingly” I mean loathsomely) called Ted Cruz a “p----.” Trump identifies crudity with populism, as if using words of four letters were a protest against prim elites. Rough language is intended to convey strength and authenticity. On both counts, it amounts to deception.

Trump employs tough-sounding language, along with the promise of war crimes (proposing killing the families of terrorists), as cover for a frighteningly feckless foreign policy. On the main humanitarian and strategic disaster of our time — the collapse of sovereignty in Syria and Iraq and the rise of the Islamic State — Trump’s answer is to farm out influence to the Russians. “Let Syria and ISIS fight. Why do we care?” Trump has argued. “And let Russia, they’re in Syria already, let them fight ISIS.”

Just to summarize, Trump is proposing for the United States to encourage a coalition of Russia, Iran and the remnants of Bashar al-Assad’s Syrian regime to fight the Islamic State and the rest of the Sunni rebels. This would recognize Russian strategic dominance over a region that still produces nearly 40 percent of the world’s oil supplies. It would concur in Iran’s bid for regional hegemony and probably frighten our abandoned Sunni allies into desperate acts (such as going nuclear). And it would reward Assad’s mass atrocities against Sunni civilians, which is a major generator of recruits for the Islamic State.

In this case, a foul mouth is meant to cover up for Trump’s ignorance and weakness. No actual enemy of the United States would be impressed by his trompe l’oeil toughness.

The whole equation of profanity with authenticity is deeply confused. There is an honesty, of sorts, in swearing when you hit your thumb with a hammer. But in presidential communication, authenticity is more than the id and tongue unleashed. Abraham Lincoln and other great presidents were authentic communicators because they treated serious things seriously, crafting policy and speeches that often challenged immediate emotional responses, expanded empathy and employed the cadences and spare language of memorable rhetoric. In the world of adults, authenticity involves thought and craft.

Trump’s intentional push against boundaries of taste is really the search for a darting spotlight, like a TV show that has gone on for a season too long and tries to ramp up controversy as a substitute for buzz. Even Trump’s authenticity, it turns out, is a lie. And his message, even dressed in the language of Sunday morning, would be an obscenity.

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