Arnold, 59, claims the actress was ready to say goodbye to the show after just one season of the reboot.
“It had to happen,” he told The Hollywood Reporter in an interview published Wednesday. “And I am going to tell you the truth, she wanted it to happen, if you saw how her tweets escalated this weekend.”
“If it hadn’t happened yesterday, this season would have been so awful for everyone every day because she would have felt like she was [being] taken advantage [of], just like when I left the show,” Arnold said.
Barr, 65, and Arnold were married in 1990 but divorced in 1994. He also worked as a writer on the show beginning in 1988.
Arnold suggested taking away Barr’s phone might have prevented her Twitter attack on Valerie Jarrett on Monday.
“ABC lost maybe $1 billion from this; this show was grinding out money hand over fist and they lost it all because somebody didn’t say, ‘Get that phone out of her hand,’” he told THR. “She’s not going to go on TV and say these things. But you put that phone in her hand and she is a loose cannon.”
He reiterated that sentiment on CNN Wednesday night, saying ABC risked a lot by not being more careful and monitoring Barr.
“I figured someone would take her phone away or monitor that, because it’s dangerous when you have that much money on a show,” Arnold said. “We have the first amendment and also we have the second amendment, but you don’t just give someone a handgun and let them walk around the stage hopefully. You got to be careful. They risked a lot. I could see it coming.”
He added, “This monkey thing is something she’s tweeted before about black people, why is it okay? It’s a meme that she and thousands of her alt right fans do. They love calling black people monkeys, it’s not a one time joke. They do it because we have a white trash racist president, and that’s a fact.”
“Roseanne and I have both known him for 30 years, and that’s an absolute fact. Instead of saying ‘Ok everybody, let’s hold on together,’ he says ‘What about me?’ That’s insane,” he continued.
When asked by Anderson Cooper if Barr had always been a Republican or if she had previously exhibited racist thoughts, Arnold said she was the opposite.
“When I met Roseanne, I just worked in a meatpacking plant in Iowa and she was older and a feminist. I had never met a feminist,” he told Cooper. “She was much more evolved than I was. I was meat packer and bouncer and part-time comic, and I learned so much from her about being liberal and that kind of thinking.”
Arnold also claimed Barr “obviously” suffered from mental illness.
“She’s having mental issues right now but that doesn’t make it ok,” he said, admitting he has also struggled with mental illness. “They had to cancel the show.”
RELATED VIDEO: ABC Cancels Roseanne, Calls Roseanne Barr’s Racist Tweet ‘Abhorrent’ and ‘Repugnant’
“Right before we got married I went to rehab for drugs and alcohol stuff and she was there for me, and then after we got married we dealt with her mental issues as a family,” he added. “And it was something she dealt with.”
As for why Barr would want the show to be canceled, Arnold claimed it was because “she didn’t get creative credit on the show, which she deserved.”
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“I’d love it if she came out and said, ‘Okay, I’ve gone too far and stepped back,'” he added. “As this weekend approached, I saw it coming.”
Barr revealed she had a multiple personality disorder, or dissociative identity disorder, in 1994, according to ABC News.
In a 2001 interview with Esquire, Barr called her disorder “a gift” and referred to herself as “we.”
“We have seven different signatures,” she told the magazine at the time. “We’ve never been comfortable saying ‘I.’ It’s something we have to do with singletons. You know, to sound normal. We consider it a gift.”
Of how she dealt with having multiple personalities, the comedian said at the time that she “was always in conflict about conflicting parts, but I’ve learned how to get them to listen to each other now.”
“I’ve learned how to get them to know they’re on the same team, that we occupy the same body, which we never knew before,” she said of her personalities.
Roseanne was canceled by ABC on Tuesday, after Barr wrote a now-deleted tweet comparing Jarrett to an ape. Barr claimed on Tuesday that she had taken Ambien before she began tweeting.
In a now-deleted tweet, Barr also wrote an apology to Jarrett, writing, “@ValerieJarrett I want to apologize to you. I am very sorry to have hurt you. I hope you can accept this sincere apology!”
Following the show’s cancelation Monday, Arnold quickly weighed in on social media.
“ABC execs figured out a way to control me,” he tweeted. “They blocked me from promoting anything on ABC because I called out Roseanne Barr & her dangerous tweets.”
Arnold also praised Disney CEO Bob Iger after ABC Entertainment president Channing Dungey announced the cancellation.
“Ton of respect for Bob Iger,” he wrote. “Tough decision with financial consequences for his company but right for America….umm…now don’t bug Bob but maybe someone else find out if I’m still banned from all of @ABCNetwork for calling Roseanne Barr out first on her racist conspiracy tweets?”