From name-calling to online spats, Rosie ODonnell and President Donald Trump have gone head-to-head with each other for nearly two decades. Now, their long-standing feud has escalated after Trump threatened to revoke the comedian's U.S. citizenship months after she fled to Ireland.During an appearance on the Irish radio show, "Sunday with Miriam," O'Donnell opened up about the contentious back and forth with the president of the United States and explained why she's "very proud" to stand up against him after all these years."He still uses me as a punching bag and a way to sort of rile his base," O'Donnell, 63, said. "And I'm very proud to be opposed to every single thing he says and does and represents. I think he's a racist, and he's misogynistic, and he's sexist, and he is a danger to women and children all over the world."ELLEN DEGENERES BACKS ROSIE O'DONNELL AFTER TRUMP THREATENED TO REVOKE HER U.S. CITIZENSHIPOver the weekend, Trump claimed that O'Donnell is a "threat to humanity.""Because of the fact that Rosie ODonnell is not in the best interests of our Great Country, I am giving serious consideration to taking away her Citizenship," Trump wrote in a post to his social media platform Truth Social. "She is a Threat to Humanity, and should remain in the wonderful Country of Ireland, if they want her. GOD BLESS AMERICA!"TRUMP THREATENS TO STRIP ROSIE O'DONNELL'S U.S. CITIZENSHIP AS HE SAYS SHE'S A 'THREAT TO HUMANITY'O'Donnell quickly responded to Trump's jab in several posts that she shared on her social media pages."The president of the USA has always hated the fact that i see him for who he is - a criminal con man sexual abusing liar out to harm our nation to serve himself," she wrote. "This is why i moved to Ireland - he is a dangerous old soulless man with dementia who lacks empathy compassion and basic humanity."The decades-long feud stems back to 2006 after O'Donnell criticized him on "The View" about his decision to be lenient toward a Miss USA winner who had been accused of drug use and other bad behavior.O'Donnell who was a co-host on "The View" at the time said Trump is "not a self-made man" but a "snake-oil salesman on Little House On The Prairie."Trump responded to the criticism by calling O'Donnell a "real loser" and "a woman out of control."CLICK HERE TO SIGN UP FOR THE ENTERTAINMENT NEWSLETTERIn 2011, after O'Donnell announced her engagement to then-girlfriend Michelle Rounds, Trump took to social media to share his thoughts."I feel sorry for Rosie s new partner in love whose parents are devastated at the thought of their daughter being with @Rosiea true loser."The next year, Trump made a surprising remark after O'Donnell suffered a heart attack."Rosie, get better fast. Im starting to miss you!" he wrote on X (Twitter at the time).In 2014, O'Donnell told People Magazine that the criticism she got from Trump was the worst bullying she had been through."Probably the Trump stuff was the most bullying I ever experienced in my life, including as a child," ODonnell said. "It was national, and it was sanctioned societally. Whether I deserved it is up to your own interpretation."Trump responded to her comments by tweeting, "RosieNo offense, and good luck on the new show, but remember, you started it!"In 2016, ODonnell publicly endorsed presidential nominee Hillary Clinton and wrote on X, "HE WILL NEVER BE PRESIDENT."Shortly after Trump claimed victory over Clinton in November of that same year, O'Donnell wrote "god help us all. i am not scared - i am sad - for all of us - for humanity."Last year, O'Donnell stayed engaged during the election, frequently posting videos on TikTok, including one when she warned people, "You can't forget what he's capable of. This is not a sane person. This is a madman. You gotta get ready for what's coming. When democracy falls, fascism takes its place."ROSIE O'DONNELL FLEES US AFTER TRUMP WIN, WONT RETURN UNTIL IT'S SAFE FOR ALL CITIZENS TO HAVE EQUAL RIGHTSIn March, O'Donnell confirmed she had fled the U.S. for Ireland."Its been pretty wonderful, I have to say," the 62-year-old said in a video on TikTok. "And the people have been so loving, so kind and so welcoming. And Im very grateful.""Although I was someone who never thought I would move to another country, thats what I decided would be the best for myself and my 12-year-old child," she explained."I miss my other kids," she added of her five grown children. "I miss my friends. I miss many things about life there at home. And Im trying to find a home here in this beautiful country. And when it is safe for all citizens to have equal rights there in America, thats when we will consider coming back."The "A League of Their Own" star added that its "heartbreaking to see whats happening politically and hard for me personally as well. The personal is political, as we all know."She added that she was "sorry" to her fans who were worried about her and missed her.LIKE WHAT YOURE READING? CLICK HERE FOR MORE ENTERTAINMENT NEWS"I just felt like we needed to take care of ourselves and make some hard decisions and follow through and now, as were getting settled, I was ready to post this and tell everybody whats going on.""The Flintstones" star said she encourages everyone to "stand up, to use their voice, to protest, to demand that we follow the Constitution in our country and not a king, not a man and we dont have cruelty as part of our governing style."That same month, President Trump criticized O'Donnell and her decision to move to Ireland during his White House meeting with Irish Taoiseach Michel Martin.When a reporter asked Irish Prime Minister Martin why he allowed the American comedian to move to the country, Trump was quick to respond."Ireland is known for very happy, fun-loving people," a reporter noted to Martin at the White House. "Why in the world would you let Rosie ODonnell move to Ireland? I think she is going to lower your happiness."Before Martin could answer, Trump chimed in and replied, "Thats true. I like that question. Do you know you have Rosie ODonnell? Do you know who she is? Youre better off not knowing."The day before Saint Patricks Day, ODonnell published a poem, "Him," on her Substack, commenting on her long feud with Trump.The Trump White House responded to O'Donnell's poem via an exclusive comment to Fox News Digital with a simple "Good riddance!"Fox News Digital's Brie Stimson contributed to this post.