One is the most cacophonous man in America, the other is the most silent. And as they head for a seemingly inevitable clash, both are living out the creeds that made them who they are.
President Donald Trump and Robert Mueller may be contemporaries but are temperamental opposites, divided most deeply by their respective contempt and reverence for the institutions of US government.
Right now, the President is doing his best to tear down the special counsel in the apparent belief that if he doesn't, Mueller will eventually do the same to him.
On Tuesday alone, Trump, with no evidence, accused Mueller of meddling in the midterm elections, of packing his team with Democratic partisans and of presiding over a "rigged" "witch-hunt" that put "spies" inside his 2016 campaign.
The raging, conspiratorial attacks on Twitter escalated a strategy orchestrated by Trump and polemicist allies in conservative media to discredit Mueller's eventual findings, to taint his probe as a Democratic plot and to unite Republican voters behind the President to secure his hold on office.
"So how do you like the fact they had people infiltrating our campaign?" Trump said at a Nashville campaign rally Tuesday night. "Can you imagine? Can you imagine? People infiltrating our campaign."
The response from Mueller? As always -- silence.
Mueller's hidden hand
Mueller may be unique in this riotous political era. Most people identified by Trump as enemies -- rival political candidates, Democratic congressional leaders or critics in the arts and the media -- feel they have no choice but to defend their reputations.
It almost always leaves them bruised and worse off. But the taciturn special counsel never fights back.
As he has done throughout his long career as a prosecutor, Mueller has put his head down, avoided the spotlight, and let his richly detailed indictments -- of 19 people and three companies -- do the talking. And he's nowhere near finished yet.
Mueller's hidden hand is one of the most oppressive forces in Washington. As witnesses trek to his grand jury, speculation mounts about his next targets and as he casts a cloud that, for all his fury and Twitter rants, Trump has been unable to dispel.
The former FBI director is investigating whether Trump or campaign members colluded with Russia during the 2016 presidential race and whether the President obstructed justice, including in the firing of his own successor at the bureau, James Comey.
Another possible reason for Trump's ire was revealed by The New York Times Tuesday in a report that said Mueller was looking into whether Trump's demands on Jeff Sessions in early 2017 to rescind his decision to recuse himself from the Russia investigation and subsequent pressure on the attorney general to resign played into the obstruction case.
As is customary with such stories, the account appeared to be based on conversations with current and former administration officials and Trump confidants, rather than originating from Mueller's office.
Mueller's reticence is not just in character. It's vital for any lingering hope he harbors of insulating his investigation from partisan politics. He may have learned from the example of Kenneth Starr, the independent counsel in the Whitewater probe who had a higher public profile and made it easier for the Clinton White House to paint him as a partisan.
Mueller's reputation for integrity, indifference to politics despite being a registered Republican and pursuit of justice over a lifetime in public service made him the ideal choice -- even for some in the GOP -- to lead the deeply sensitive investigation into the Trump campaign.
The former FBI director's life principles, revealed at a commencement address at a Massachusetts boarding school last year in a rare public appearance seem almost quaint in modern Washington. But they've been the bedrock of his life as a prosecutor and more than a decade heading the FBI.
"You can be smart, aggressive, articulate and indeed persuasive, but if you are not honest, your reputation will suffer, and once lost a good reputation can never, ever be regained," the Vietnam-era decorated combat Marine said.
"As the saying goes, if you have integrity, nothing else matters, and if you do not have integrity, nothing else matters," he added.
Blurring the truth
But Mueller's failure to defend himself, or to send surrogates on to television to parry the fierce White House attacks have also offered an opening to Trump.
Just as Mueller is acting as he always has in relentlessly pursuing the investigation, Trump is doing what he's always done -- blurring the truth and using his marketing expertise to sell a preferred reality about the Russia investigation.
"He's a very shrewd guy, he's a tremendous salesman," Trump biographer Gwenda Blair told CNN's Brooke Baldwin Tuesday. "He wants to and arguably needs to undermine the legitimacy of that investigation, he is undermining and delegitimizing any chance he gets."
The President has fired round after round of politicized rhetoric at Mueller -- and it's working. Polls are beginning to show that the special counsel's reputation is tarnished.
A CNN/SSRS poll this month showed that 44% of voters approve of how Mueller is handling the investigation -- down four points from March. Only 17% of GOP voters approve of the special counsel now, down from 29% in March.
Trump has worked to undermine the credibility of the investigation by repeatedly saying there is "no collusion" with Russia and by claiming the FBI abused surveillance law. He has repeatedly warned it is a "deep state" witch hunt, accused ex-President Barack Obama of wiretapping Trump tower and coined the phrase "spygate" to his campaign was infiltrated by FBI agents.
If the integrity and reputation of America's judicial system, the FBI and the Justice Department are tarnished along the way, so be it.
The President's new lawyer Rudy Giuliani has taken up the assault with relish, saying Trump is not a perpetrator but the victim of circumstances that compare to the most notorious political scandal in American history.
"Everything wrong with the government spying on a candidate of the opposition party. That's a Watergate," Giuliani said on Fox News Sunday last weekend.
Giuliani also revealed the purpose behind the Trump campaign's effort to dismember Mueller's reputation for integrity.
"What we're doing here, it is the public opinion, because eventually the decision here is going to be impeach or not impeach," Giuliani told CNN's Dana Bash on "State of the Union" on Sunday.
So Trump hopes to build a wall against impeachment -- by making it impossible for GOP lawmakers to defy the sentiments of their voters and by coalescing in any impeachment proceedings.
In one sense, the Trump administration's approach is nonsensical.
If the President is confident that he is not guilty of obstructing justice of conspiring with Russians to meddle in the 2016 election, he ought to welcome Mueller's reputation for integrity.
After all, the special counsel's reputation for integrity would offer Trump a political gold mine if he is exonerated.
So it's no wonder the Trump attacks are fueling suspicions that the President does indeed have something to hide.
That suspicion also points to the great unknown of the entire showdown between the President and the special counsel.
Mueller knows what he has -- Trump and his allies cannot be sure -- hence their desire to launch a preemptive strike against him.
But while he's silent now, Mueller -- whether with a report about presidential wrongdoing to the Justice Department or more indictments of Trump associates -- could roar the loudest.