MAUREEN DOWD: For whom the Trump trolls

He proselytized against drinking and smoking, warning his kids away from those vices. Even with his casinos, Trump wasn’t a gambler, either, saying he’d rather own slot machines than play them.

And yet, in a strange twist, Trump has ended up an addict.

Lanier, who met Trump a couple of times back in the real estate developer’s New York heyday, thinks the president’s addiction to tweeting is rewiring his brain in a negative way. As Trump picks up speed on Twitter, the Oval Office is becoming a Skinner box. Like other “behavior modification empires,” as Lanier calls social media sites, Twitter offers positive reinforcement for negativity.

“Twitter addicts take on this kind of nervous, paranoid, cranky quality, sort of itching for a fight,” Lanier said in an interview. “Trump used to be in on his own joke, and he no longer is. He’s just striking out every morning, fishing for somebody to harass or seeing who’s harassing him.

“I do think it creates a terrifying situation because somebody who is addicted is easy to manipulate. It’s easier for the North Koreans to lie to him than if he wasn’t an addict.”

And the hostility and insensitivity that so easily flow from his fingers now define his immigration policy.

On the occasion of America’s 242nd birthday, we must ask who we are, if we can see accounts of infants snatched from their parents and returned covered in lice, and not worry about our country’s soul.

Trump has certainly made political discourse more crude and belligerent. But is he making the whole country meaner, coarser and less empathetic? Or was the pump primed for a political figure like him because the internet had already made America meaner, coarser and less empathetic? Did they happen simultaneously?

Manjoo told me: “Now when you log in, they show you the most interesting tweets you missed while you were away. They highlight the tweets of people arguing, the big news brawls of the day, as a way to engage the rest of the audience. That makes it a meaner place.”

On its company blog, Twitter said it was inspired by Cortico, a nonprofit research organization that is trying to measure “conversational health” with four indicators: shared attention, shared reality, variety of opinion and receptivity. Not exactly the attributes we see in Trump.

Be best!

Art Markman, a psychology professor at the University of Texas at Austin who has lamented the extraordinarily aggressive online comments at media outlets, hopes people will resume a sense of decorum when they realize “there’s very little long-term profit from a viral tweet.”

“We don’t have to cater to those meanspirited instincts,” he said. “We can be better than that.”

But I don’t think Trump can. He figured out how to dominate Twitter, not with the cool-kid arch style of making fun of someone, but by being school-yard-bully mean.

His tweets propel the story on cable news and shape the narrative for reporters — who are addicted to the First Addict.

For Trump, who is also an attention addict, that is about as holistic as it’s going to get.