In a year of floors falling away under one’s feet — such as the assumption that nearly all Americans demand a minimal level of civility in public life — the Corey Lewandowski story represents one more gobsmack. That Donald Trump stands by the belligerent Lewandowski tells us more of what we already knew about Trump and also hints at the coward beneath the blowhard.

First, the battery. The campaign manager — not a volunteer, not even a hired security guard, but the honest-to-goodness campaign manager — nearly shoved reporter Michelle Fields to the ground and inflicted bruises on her arm. The campaign at first suggested that there was a mistake: Lewandowski mistook Fields, who worked at the time for the pro-Trump website Breitbart.com, for a member of the mainstream media. Oh, so that makes shoving OK? But the campaign quickly reverted to outright lies. Hope Hicks, a Trump campaign spokesman, said that Fields’ account was “entirely false.” Trump himself offered that “maybe she made it up.”

The following day there was an audio recording of the Terris/Field conversation immediately after the incident, which further confirmed her account. And then there were videos, one of which was enough to convince the police to bring battery charges. Never mind. In the morality-free Trump zone, facts are optional.

So the battery is an established fact shamelessly denied. And then there is the character assassination. Trump has suggested that Fields was an attention seeker, and sneered that she’s “not a baby, OK?” This is classic Trump attacking those he has already wronged. Asked in an early debate about the people left holding the bag after his four bankruptcies, he dismissed them, saying they were “big boys and girls.” Actually, many were electricians, carpenters and other working people who couldn’t afford his fancy lawyers.

Perhaps Trump’s fondness for Lewandowski is not in spite of his henchman’s willingness to get physical but because of it.

Trump seems more than usually frightened of protesters. To be sure, every candidate gets serious threats, and doubtless Trump has received some. But his threshold for feeling vulnerable seems unusually low. Before a rally in Iowa, he was told that some protesters might throw tomatoes at him. He was sufficiently alarmed to tell the crowd: “If you see somebody getting ready to throw a tomato, knock the crap out of them.” For tomatoes.

On another occasion, Lewandowski waded into the crowd and grabbed a protester by the collar. Trump approved of this maneuver, too, explaining — if that’s the right word — to CNN’s Anderson Cooper that the man’s sign contained very bad words. Non sequitur.

The Trump campaign has changed its story several times about Michelle Fields. The latest, on CNN Tuesday night, featured Trump justifying Lewandowki’s manhandling of Fields because she approached the TV star armed with a pen “which is very dangerous.” Tomatoes, Bics, is there no end to the threats against Trump?

Donald Trump avoided the draft by claiming bone spurs in his heels, which somehow didn’t keep him off the ski slopes. Yet he had the gall to disparage the heroism of John McCain.

Trump is a physically large man with the courage of a mouse. Like many cowards, he loves tough talk, but he prefers to issue threats from the comfort of his private jet and to let bullyboys like Lewandowski actually get their hands dirty. Purely as a matter of national hygiene, Lewandowski should be fired. But more importantly, so should his boss.