It now seems all but certain that the presidential election will see Donald Trump face off against Hillary Clinton.

We find ourselves at the tail end of a brief period of clarity. For the past few months, virtually everyone outside of the 40 percent of Republican primary voters who carried him to victory has agreed that Trump is not fit to be president.

Marco Rubio called him a "con man." Mitt Romney called him "a phony, a fraud." Cruz called him an "amoral pathological liar" and said if he is elected "this country could well plunge into the abyss." Lindsey Graham said Trump would lead to "another 9/11." David Brooks called him "epically unprepared to be president." George Will said that "his running mate will be unqualified for high office because he or she will think Trump is qualified." The house organ of conservatism, National Review, condemned him in florid terms. A Super PAC was created just to stop him.

This Clinton camp video is effectively narrated by Mitt Romney https://t.co/E4Iynf1SuZ — Gabriel Debenedetti (@gdebenedetti) May 4, 2016

No one has captured the case better than longtime conservative political analyst Jay Cost:

[<a href="//storify.com/SeanTrende/jay-cost-goes-nuclear-on-trumpkins" mce_href="//storify.com/SeanTrende/jay-cost-goes-nuclear-on-trumpkins" target="_blank">View the story "Jay Cost goes nuclear on Trumpkins" on Storify</a>]

As Cost emphasizes, the issue here is not (merely) ideological — it's about basic fitness and competence. A man with Trump's temperament and habits could do real, lasting, no-joke damage as the leader of the free world.

Hillary Clinton, for all her flaws, has demonstrated a basic level of competence. She understands how policy and government work. She's not openly racist; she hasn't encouraged street violence. There's no risk that she would disrupt the international order or cause an economic crisis out of pique.

That's a really, really low bar. But it's the only bar she has to clear in this contest. Almost irrespective of what you think of Clinton's politics or her policies, she is manifestly more prepared to run the federal government than Donald Trump.

The number of people who recognize this elemental fact about the election, however, has probably already reached and passed its peak. It will decline from here on out. The moment of clarity is already ending.

The political ecosystem needs two balanced parties to survive

Why is clarity passing? Because it appears Trump is actually going to be the Republican nominee. It's really happening. And the US political ecosystem — media, consultants, power brokers, think tanks, foundations, officeholders, the whole thick network of institutions and individuals involved in national politics — cannot deal with a presidential election in which one candidate is obviously and uncontroversially the superior (if not sole acceptable) choice. The machine is simply not built to handle a race that's over before it's begun.

There are entire classes of professionals whose jobs are premised on the model of two roughly equal sides, clashing endlessly. The Dance of Two Parties sustains the consultants and activists.

That giant clicking sound is 10,000 Republican consultants and activists deleting their #NeverTrump tweets. — Paul Mitchell (@paulmitche11) May 4, 2016

Trump campaign now being flooded with offers from seasoned operatives to help the campaign, Rick Wiley tells me. — Dana Bash (@DanaBashCNN) May 4, 2016

It sustains the party hacks and grifters.

.@realDonaldTrump will be presumptive @GOP nominee, we all need to unite and focus on defeating @HillaryClinton #NeverClinton — Reince Priebus (@Reince) May 4, 2016

There's a lot about Donald Trump that I don't like, but I'll vote for Trump over Hillary any day. — Ari Fleischer (@AriFleischer) May 4, 2016

And it sustains the media, which is what I want to discuss below.

Among all these classes of professionals, all these institutions, that whole superstructure of US politics built around two balanced sides, there will be a tidal pull to normalize this election, to make it Coca-Cola versus Pepsi instead of Coca-Cola versus sewer water.

The US political system knows how to play the former script; it doesn't know how to play the latter. There's a whole skein of practices, relationships, and money flows developed around the former. The latter would occasion a reappraisal of, well, everything. Scary.

So there will be a push to lift Donald Trump up and bring Hillary Clinton down, until they are at least something approximating two equivalent choices.

It's not a conspiracy; it won't be coordinated. It doesn't need to be. It's just a process of institutions, centers of power and influence, responding to the incentive structure that's evolved around them. The US political ecosystem needs this election to be competitive.

The media cannot countenance a lopsided race

No institution needs a competitive election more than the media, especially what remains of the "objective" campaign media. Imagine writing this headline:

Trump, bad candidate, likely to lose

Now imagine writing it again and again for six months — and watching your web traffic dwindle into nothing. Sad!

The campaign press requires, for its ongoing health and advertising revenue, a real race. It needs controversies. "Donald Trump is not fit to be president" may be the accurate answer to pretty much every relevant question about the race, but it's not an interesting answer. It's too final, too settled. No one wants to click on it.

What's more, the campaign media's self-image is built on not being partisan, which precludes adjudicating political disputes. How does that even work if one side is offering up a flawed centrist and the other is offering up a vulgar xenophobic demagogue?

It would be profoundly out of character for reporters to spend the six months between now and the election writing, again and again, that one side's candidate is a liar and a racist and an egomaniac. It would be uncomfortable, personally and professionally.

What we've learned today abt life thru Nov if Trump wins:some reporters can't be objective abt him & left/right critics will sound the same — Mark Halperin (@MarkHalperin) April 27, 2016

It's true that the media has been uncharacteristically blunt in its criticism of Trump during the primary, mainly because almost every source it considers legitimate hates Trump, including the Republican establishment. To date, the anti-Trump position has been safely inside the Washington consensus.

That will change once the GOP apparatus inevitably swings around behind Trump and begins accusing journalists who write critical stories of bias. If there's one thing the GOP apparatus knows how to do, it's ensure that there's always another side, that reporters get smacked every time they move past "one hand, other hand" coverage.

Already we've seen reporters leap at the Trump "pivot" story several times, though Trump's newfound presidential tone never seems to last even a full 24 hours.

It will not take much for "new, grown-up Trump" stories to take hold once he is the nominee. The media and the GOP apparatus both need those stories, the former for "balance," the latter for paychecks.

In short order, Trump's obvious unfitness for office — today widely acknowledged across both parties and in the mainstream media — will become a partisan observation, something Democrats say. Consultants from the two parties will sit across from one another on cable news shows and squabble about it, as nature intended.

To the extent that Trump can't be lifted, Clinton will be brought down

Just as the media will need to elevate Trump, it will need to bring Clinton down. Going after Clinton will be journalists' default strategy for proving that they're not biased. They will need opportunities to be "tough" toward Clinton, or at least to engage in the kind of performative toughness valued in campaign journalism, to demonstrate their continued independence.

Trump will give them opportunities. And it's not going to be through policy critique, a domain in which Clinton towers over him. It's going to be through tawdry, nasty shit.

Consider the attacks Trump has used to triumph in the primary: Cruz's father helped kill JFK; Cruz is not eligible to be president; Rubio is an effete liar who sweats too much; Kasich is a disgusting eater; Jeb Bush has low testosterone; Fiorina has an unpleasant face. His nickname for Clinton is already "crooked Hillary." He's already dredged up her husband's affairs and her alleged role in them.

Consider what Trump will do when he's behind, being bested by a woman, at risk of national humiliation, struggling to unite a party that is connected to him only through a shared hatred of Clinton. The mind boggles.

Will the Washington press corps chase after ridiculous personal attacks and conspiracy theories regarding Hillary Clinton, whispered into their ears by right-wing hacks?

Ha ha. Have you met the Washington press corps? They have been doing that since the early 1990s. Clinton rules mean guilty until proven innocent, then and now. The Washington media is a machine that transforms crap about Clintons into headlines, and Trump is a bottomless supply of crap.

Along with that, Clinton being Clinton, and Clintonworld being Clintonworld, there is likely to be no shortage of missteps, malapropisms, unforced errors, and poorly chosen surrogates to keep the media busy even without Trump's help. Stories purporting to (finally) bring Clinton down never lack for clicks. She is, after all, the most disliked national politician in American life ... except Donald Trump.

So there you have it: an obvious choice that numerous institutions and individuals are committed to making as difficult, as unpleasant, and as drawn-out as possible. It augurs a substance-free, policy-averse, crap-happy campaign season, degraded even by the diminished standards of contemporary US politics. Wake me when it's over.

This is why Donald Trump can't win a general election