You may or may not have noticed, but the 2016 presidential campaign has entered a new phase — perhaps even a new dimension. It is new, not just for this year's already extraordinary campaign, but for American political discourse.

That is because on Friday, Donald Trump brought forth what may well be the most preposterous falsehood anyone has attempted to peddle in our political life. Think that is hyperbole? Feel free to counter with something to match it. Seriously.

Trump spent five years as the indisputable point of the spear for the "birther" movement. That means he transitioned from reality TV star to presidential candidate largely by questioning President Obama's birth certificate — asserting that the first black president was really born overseas and therefore ineligible for the Oval Office.

After all that, and after keeping his actual views on the subject a secret as late as Thursday, Trump reversed himself overnight. He said the president was born in the U.S., that he had been the one to lay the matter to rest, and that the whole controversy had begun with — wait for it — the Hillary Clinton campaign.

If you are a fan of Bible stories, you might expect at this point that the earth itself would open, and Donald Trump would be swallowed up. (Check out the fate of some false witnesses in the book of Numbers 16:31.)

The earth did not open, but at least a portion of it did move on Friday. It was the portion where many of us as journalists try to stand. We have lived in the faith that if we report what the candidates say, and do it with accuracy and fairness, our audiences will judge for themselves what is true and what is not.

But what happens when one candidate defies all notions of fact and fiction? When one candidate declares the moon is the sun and vice versa?

In this campaign, it has become obvious that it's not enough to say, "His opponent denied it." It has called for far more than traditionally boilerplate treatment of telling both sides. Several in the media during this campaign have started to move beyond "he said, she said" stories, an expression that predates both Donald Trump and Hillary Clinton.

Books have been written about these rules, pro and con. In addition to stories labeled "fact checking" — something that had been between a cottage industry and a sub-genre of journalism — reporters have moved to fact check in real time on air and online.

The old rules have been rendered moot and journalistic restraint tested by the strategy and tactics and stupendous success of one candidate. Donald Trump has found it possible not only to circumvent the media and defy them, but to exploit their power and discredit their judgment at the same time.

Consider the birther business, perhaps the most debunked allegation in a generation. Having gained attention for himself over a five-year campaign of misinformation, Trump thinks he can now abandon it, cast himself as some sort of truth seeker and attach all the opprobrium to his opponent instead. Surely even the notorious masters of 20th century propaganda would be in awe.

If this is the kind of behavior that has been associated with the Trump campaign since its inception, it is still stunning to see it defended by Republican Party leaders such as its chairman, Reince Priebus, who surely knows better, on Sunday morning talk shows.

To be clear: Neither Hillary Clinton nor her campaign in 2008 pushed the birther story. Needless to say, comparing that to Trump's performance on the issue is not just a smokescreen, but a distortion and an embarrassment.

The moderators of those venerable weekend chat fests have long enjoyed more leeway than straight-news reporters. Some regard them as a kind of "editorial page" for their networks. And so the likes of John Dickerson on CBS and Jake Tapper on CNN and others were out there on Sunday using the L word in a way one almost never hears in the broadcast media. The word "lie" is, in fact, a word we are taught to avoid as journalists, a word freighted with value judgment and fraught with political peril.

But that practice has been under tremendous pressure in 2016, and it's crumbling. Journalists are increasingly willing to throw the penalty flag, say the L word, or label statements false — and not just in stories labeled as fact checks.

Even CNN, which has lavished airtime on the Trump campaign for more than a year, has even begun displaying lower-third banners on screen when his statements are demonstrably untrue. It can be jarring at times to see a Trump line followed by a parenthetical ("False") or ("It's Not").

This all seems quite new, but there are antecedents.

In 1954, the rambling wreck who was Joe McCarthy picked a fight with the U.S. Army over the promotion of a dentist. McCarthy, the Red-baiting Republican senator from Wisconsin, seemed convinced the dentist was a communist and a spy. People in the media had been frustrated by McCarthy's tactics and bluster for years, but the lunging attack he launched on the Army finally broke the dam. Today, we can look back and see that the senator who spoke of finding scores, even hundreds of communist infiltrators in government in fact produced not a single one.

And in 1968, a generation of journalists who had covered the second world war or been raised on its lore lost their faith in the U.S. military adventure on Vietnam. Having told their audiences for years that the U.S. was fighting communism and defending the American way, they found themselves saying the war was a hopeless stalemate and the justification for it a sham. Something similar made its way to the forefront of the coverage of the Iraq War in the middle of the last decade.

But as a rule, in recent decades, we in the American media have been content to enjoy our share of the nation's peace and prosperity — and yes, even a modicum of prestige. We have been among those who flourished in the American century and enjoyed its fruits. Maybe that is why so many of us missed the rising tide of profound alienation in the country today — the deep despair over our economic prospects, our cultural values and, yes, our political system.

That is our burden, our mea culpa. We will bear that judgment. But that does not mean we should sit out the rest of this election, either with respect to the facts or in the matter of judgment. We will continue to listen to all sides and assess all sides and attempt to make sense of conflicts. But we must also call things by their right names.

The current case is simply without precedent. Trump has long insulted leading figures in public life, including rivals for the Republican nomination and nonsupportive members of his own party. This weekend that group came to include former Defense Secretary and CIA Director Robert Gates (whom Trump called "a clown," while asserting that he, Donald Trump, knew far more about defense, intelligence and security).

Some will say all this falls within the bounds of acceptable political behavior, especially in our time and in our social media sensibility. But some of us are still journalists and still feel a responsibility. And when someone tells us the sun rises in the west and sets in the east, that's just not OK; it's not business as usual.

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