It always seems like the current election — no matter which year — is the nastiest, longest and most brutish.  

But Trump vs. Clinton — the World War III of presidential elections — promises to put them all to shame. Sure, Trump still has a fight on his hands to win the GOP nomination outright. And Clinton will likely have a bowed but undeterred Bernie Sanders picking away at her for the next few months.  

But the matchup that has seemed almost inevitable since late last year remains the most likely, and most combustible, scenario.  

“It will be the most vicious … campaign in American history. It will pale to anything we’ve ever seen before, and will be demoralizing,” one Democratic strategist told me Tuesday night.  

Clinton understands that she’s better off appealing to Americans’ better angels in the face of Trump’s instigation of anger and violence.  

“Our next president has to bring our country together,” she said after hammering out delegate after delegate on Tuesday night. “When we hear a candidate for president call for rounding up 12 million immigrants, banning all Muslims from entering the United States — when he embraces torture, that doesn’t make him strong. It makes him wrong.”  

That’s a weak-sauce contrast compared to Trump’s pithy (and sometimes filthy) jabs and roundhouses—not to mention the actual punches that are thrown at his rallies.  

But make no mistake: Clinton’s superPACs, her battle-forged surrogates and the Democratic Party apparatus are loading up to try to annihilate Trump.  

It’s a playbook we’ve seen before: A Democratic candidate with low approval numbers carpet-bombs his or her opponent until that rival’s ratings drop even lower. The prime example is Harry Reid against Sharron Angle in 2010.  

And no matter how much Clinton might benefit from the contrast of being the high-road candidate, it’s not in her nature, her husband’s nature or the nature of the political mercenaries around her to back away from a political fight.  

Trump, for his part, has shown only one basic political instinct: Destroy. He is fomenting the anger already present in many of his supporters.  

He says he’s channeling his backers, not inciting them.  

“I’m just the messenger,” he said on NBC’s “Meet the Press” on Sunday .  

On Tuesday night, he was in unifying mode, declaring “We have to bring our party together” and praising defeated rival Marco Rubio as someone who has “a great future.”  

But he couldn’t resist identifying the emotion that is fueling his campaign.  

“There is great anger, believe me, there is great anger.”  

The man who helped lead the “birther” movement against President Barack Obama, who called Ted Cruz an epithet for a female body part and derided Rubio as “Little Marco” doesn’t sound like he’s in any mood to give quarter to Clinton.  

And he’s shown he’s willing to go after other Clintons, too.  

“She’s got one of the great women abusers of all time sitting in her house, waiting for her to come home for dinner,” Trump said of former President Bill Clinton earlier this year.  

This is going to be ugly—very ugly.  

In an arms race, mutually assured destruction is a deterrent. In this political race, it will be the raison d’etre.

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