WASHINGTON (CNN) -- Rudy wouldn't be Rudy if he backed down.
But by amplifying his charge that President Barack Obama doesn't love America, former New York Mayor Rudy Giuliani appears ready to risk sullying the powerful mythology that grew around his leadership when he steadied and steeled the nation in the terrible, confusing time after 9/11.
Since those fleeting days when he was a unifying figure, Giuliani has more often dealt in waspish rhetoric and savage mockery -- especially of a president he says has "failed."
"America's Mayor" has gone rogue, lashing out at Democrats and liberal orthodoxy on the war on terror and saying, for example, during the Ferguson controversy last year that the biggest danger to a black child was not from a white police officer but from another African American.
The latest firestorm over Obama's patriotism may complete Giuliani's political journey from the center left of the Republican Party to the conservative jungles where Sarah Palin and Donald Trump roam.
"Rudy has devolved into this red meat Republican base ideologue who periodically seems to need self identification," said Douglas Muzzio, a political scientist at Baruch College and a New York City media commentator. "Maybe it is Rudy in his dotage, where he has lost whatever boundaries he once had. He sounds like a bitter old man."
Giuliani seems to be relishing his moment back in the spotlight.
But he's also causing awkward moments for Republican candidates limbering up for a crack at the presidency in 2016 -- a fact the White House was quick to exploit on Friday.
"It's sad to see when somebody who has attained a certain level of public stature, and even admiration, tarnishes that legacy so thoroughly," said Obama's spokesman, Josh Earnest. "And the truth is, I don't take any joy, or vindication, or satisfaction from that. I think, really, the only thing that I feel is I feel sorry for Rudy Giuliani today."
Democratic National Committee Chairman Debbie Wasserman Schultz also joined in, seeking to use Giuliani to frustrate the GOP's effort to short circuit controversies which could tarnish the party's image.
"Now is the time for its leaders to stop this kind of nonsense. Enough," she said.
Giuliani's blast, delivered in a closed door Republican dinner, and repeated in a media tour, centers on a claim that Obama was not brought up to "love" his country like most Americans.
It's a familiar charge from the conservative fringe, that Obama is somehow different and doesn't view America as an exceptional paragon but is obsessed with apologizing for its failings.
"I do not believe, and I know this is a horrible thing to say, but I do not believe the president loves America," Giuliani was quoted as saying by Politico.
Asked by Fox News host Megyn Kelly Thursday whether he wanted to apologize, Giuliani replied: "Not at all. I want to repeat it."
"I don't feel this love of America," Giuliani said. "I believe his initial approach is to criticize the United States."
Giuliani dug in further in an interview with the New York Times, rejecting the idea that his remarks were born of racism.
"I thought that was a joke, since (Obama) was brought up by a white mother, a white grandfather, went to white schools, " said Giuliani. "This isn't racism. This is socialism or possibly anti-colonialism," said Giuliani.
Far from being chastened, Giuliani, who wore a conspiratorial grin on Fox News, seems gleeful in the firestorm. His behavior might be explained by a boxing maxim he was taught as a boy, which may also shed light on his calmness on 9/11.
"My father taught me ... when you get hit in the face for the first time, you're going to panic," Giuliani said in an interview with Forbes magazine in 2011. "Instead of panicking, just accept it. Stay calm. And any time anybody hits you, they always leave themselves open to be hit."
Giuliani's actions may be both a glimpse at his political philosophy and reflect a decision to wade into the political echo chamber to solidify his standing among a certain group of conservatives.
"He understands political posturing, he understands the effectiveness of rhetoric," said Errol Louis, a CNN political commentator from New York. "He clearly wants to play a role on the national stage. I guess he has chosen the role of bulldog -- go after the president, attack him, make wild accusations."
With a failed presidential campaign behind him, and having been out of office for a decade-and-a-half, it may be that Giuliani sees his future on the conservative talk circuit.
"To the extent that Giuliani will be involved in the game moving forward, it will be as a commentator or an analyst," said Costas Panagopoulos, a campaigns expert at Fordham University, New York. "In order to do that successfully these days, it helps to be controversial, sometimes inflammatory. I am not surprised that he has become increasingly forceful in his comments in the media. He is convinced that will help him."
Giuliani has rarely been known to back down. He was a Yankee fan growing up in Brooklyn, a ruthless prosecutor who took on unions and the Mob and a hard driving Republican who ran a liberal city.
When he awoke on September 11, 2001, Giuliani was a polarizing figure with a large ego and a sharp tongue. He might have purged New York street crime but was starting to grate on the city's nerves at the end of his second term.
Within hours, with a staggering display of calm, purpose and leadership, he had recast himself as a modern-era Winston Churchill, steadying and inspiring his people in their darkest hour. His heroics were such that he became one of those politicians who become known by a single name.
Marching up Broadway, he grabbed a mike and told people to evacuate southern Manhattan. He conjured up national resolve and resistance, as a country waited hours to see its president, out of sight on Air Force One.
"People tonight should say a prayer, for the people that we have lost, and be grateful that we are all here," he said in a late night press conference 12 hours after the Twin Towers came crashing down in a toxic cloud of fire and ash. "Tomorrow New York is going to be here and we are going to rebuild and we are going to be stronger from before."
Making Giuliani its Man of the Year, Time Magazine said: "When the day of infamy came, Giuliani seized it as if he had been waiting for it all his life."
But he struggled to meet huge expectations. His 2008 presidential campaign was a bust, plagued by poor organization and his liberal views on social issues that conflicted with the conservative base.
But there was also a sense that he was playing the September 11 card too much: Joe Biden's crack that there were "only three things he mentions in a sentence, a noun a verb and 9/11" was funny because it bore more than a ring of truth.
That was years ago now. But while his years of elective office are behind him, Giuliani still seems to pine for the political spotlight. So he has every incentive to keep this row going as long as he can.
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