Donald Trump’s biggest, and most famous, Twitter troll is absolutely horrified that Donald Trump has a better than decent shot at soon becoming the most powerful person in the world.

“He’s a monster who wants to destroy America,” Danny Zuker flatly told The Daily Beast. “Now, the stakes are obviously somewhat higher than when it was just an orange reality-TV star being the total embodiment of the worst of America’s id. So, it’s kind of dangerous. I don’t think it is the least bit funny.”

Zuker is a TV writer and producer, specializing in network sitcoms. His credits include Just Shoot Me!, Stacked, The Arsenio Hall Show, Roseanne, and (currently) ABC’s multicultural hit Modern Family. Ever since early 2013, he has garnered media attention for something other than his Emmy-winning work: namely, his Twitter war with Donald J. Trump.

It all started three years ago, when Zuker was sitting around and realized that he—like so many Hollywood liberals with Internet access—did not find Trump’s self-aggrandizing and politically conservative tweets amusing. (For those keeping score, Zuker has about 264,000 followers, versus @realDonaldTrump’s roughly 6.36 million.)

“I’ve hated Trump ever since the Central Park Five,” Zuker said, referring to when Trump in the late 1980s called for the execution of five black youth accused of attacking and gang-raping a female jogger. (The defendants received different sentences and served between six and 13 years behind bars before new evidence of coerced confessions emerged, leading to their convictions being vacated in 2002.)

“From the moment I was first on Twitter, I don’t like to troll,” Zuker claimed. “I usually just troll my own kids on Twitter.”

Then, for whatever reason, Zuker started hate-tweeting at Trump—and The Donald started noticing that this sitcom writer was being mean to him on the Internet.

“I just got lucky—he just responded to me,” Zuker recalled. “There is no one I know in comedy who couldn’t have done what I did. It was a little bit like dunking on a toddler…He engaged over the most innocuous tweet I had ever sent. He was tweeting about the ratings for Celebrity Apprentice, so I tweeted back…that [his show] was beaten by a Family Guy rerun. And off of that, he exploded. And then [our Twitter fights] became about everything.”

In the time since, they’ve yelled at each other on Twitter about anything from physical appearance to racial politics. Click here and here for a fuller history, and look below for a sample, starting with the Trump tweet that launched their protracted, bloody tweet-war:

Trump would soon take his sniping off Twitter as well. In May 2013, Zuker says, Trump’s executive assistant at the Trump Organization sent him an email. “I hope you are doing well,” it read. “Mr. Trump would like you to see the attached note. Thank you and have a great day.”

The attachment was a PDF of an interview Zuker had granted to a friend, that included in the introductory paragraphs a reference to “Donald Trump.” Trump highlighted his own name in yellow, signed the page, and wrote (perhaps sarcastically), “GOOD JOB!”

“I wrote back, ‘Thank you?’ and that I didn’t know what this means, but I still don’t like you,” Zuker said. “It’s weirdly like he wanted to be buddies with me. Strange and weirdly creepy. Like, this was a small interview I did for a friend of mine and he spent time looking for it and then finding me.”

Of course, this all began as a mildly amusing story about a reality-star real-estate mogul having a petty Twitter tiff with a Modern Family staffer and Hollywood lefty. Today, Trump is no longer just another bloviating, Obama-hating, birther punchline. He is no longer a mere pop-culture fixture.

He is the 2016 GOP presidential frontrunner (by quite a lot), and has cleaned up in New Hampshire, South Carolina, and Nevada. He racked up seven Super Tuesday victories. A Republican Party nomination of Donald Trump is looking ever increasingly inevitable.

And this has Trump’s greatest Twitter troll legitimately fearing for his countrymen.

“[Trump’s message] is 100-percent fascistic,” Zuker said. “I dunno, maybe I jump to conclusions, but when you say, ‘Sieg Heil!’ at a Trump rally, maybe you have fascist leanings. I’m sorry, maybe I’m just another left-wing Jew.”

In the summer after this bitter personal feud kicked off, Zuker wrote an op-ed for The Hollywood Reporter on “how to win a Twitter war.” And for the last couple of years, the skirmishes between him and Trump have been mostly one-sided.

“He blocked me in, like, 2014, I believe,” Zuker said. “He’s occasionally retweeted someone who’s come after me. But since he announced [his run for president]…I was actively avoided. To his credit, he was smart enough to realize that this was a zero-sum game.”

The Trump campaign did not respond to The Daily Beast’s request for comment regarding the Republican frontrunner’s Modern Family Twitter troll.

Zuker says that when the feuding began, he was worried he might get in trouble with his Modern Family and ABC colleagues.

“When it first blew up, I became a little bit nervous because I had no desire to drag the show into it,” he said. “But he’s such a baffoon, that people were very happy to have me go after him. And then he went after Modern Family.”

The showrunners and cast members Eric Stonestreet and Julie Bowen were delighted. Sofía Vergara, a Latina actress, “absolutely loved it,” Zuker claims.

The nasty tweets also won the sitcom writer/producer new fans south of the border. Late last year, when Zuker went to Monterrey, Mexico, to speak at an event (a “Mexican SXSW,” as he described it) organized by Movimiento Nomadx, he was presented with a Donald Trump piñata.

“I was talking to a bunch of young urban professionals [in Mexico] and I remember them saying, with a certain degree of sadness, that the things that Trump was saying, that was never what really frightened them,” Zuker said. “After all, he was a clown. It was when [the news] turned the cameras around—at the crowds of people cheering.”

“And the anti-Muslim rhetoric is just as dangerous,” he added.

Zuker (who is, unsurprisingly, on Team Hillary for this election) says he has a connection to another Republican presidential contender—one whom he is far more fond of than The Donald.

“Chris Christie was sorta like an older brother to me [growing up in New Jersey],” he remarked. (Zuker knew Christie, who recently endorsed and is now campaigning for Trump, through the Jersey governor’s brother.) “We chat sometimes. And I’ve talked to his brother about this election…All the Republicans, Chris included, probably made the mistake of not slapping [Trump] down when they had the chance…They were all enormous pussies with him, in my opinion…and the press too.”

Zuker called out MSNBC, among other outlets, for playing too nice with Trump.

“When Fox New is hitting [Trump] harder than MSNBC, you really do have to examine what you’re doing,” he commented. “When Megyn Kelly has the temerity to go after him, he ran away like a little fucking pussy.” (Zuker stressed that his word choice was an allusion to when Trump called his rival Sen. Ted Cruz that term.)

When asked if he would ever write a character inspired by, or based on, his enemy, Zuker offered up a hard “no.”

“I am more than happy to attack him rather than glorifying him in any way,” he insisted. “He’s a caricature already. I don’t think I can write a bigger asshole.”

As this “asshole” gets closer and closer to the Republican nomination (and thus closer to the White House), Zuker is still having trouble wrapping his head around it.

“The word ‘surreal’ gets used a lot, but yes—it is,” the writer said, sighing. “I’m like a guy who you just told has cancer. I refuse to believe he will become president. Maybe I am just in a denial phase. I still believe a guy who has insulted this many Americans, of all shapes and sizes…cannot become president. I’ve been wrong every step of the way, though, and I’m prepared to be wrong again… And I’ve heard Australia is a beautiful country.”

Zuker clarified that he is not actually planning to pull a “move to Canada” if Trump indeed makes it to the general election and wins. He loves his country too much, and, as a comedy writer, he would have a civic duty to document the Trump administration, however long such an enterprise would last.

“I’m sure he’ll be great with the nuclear codes,” Zuker concludes, with tongue firmly ensconced in cheek.