Illegitimate and corrupt. Using the FBI as a political weapon and America’s secret police. “Secret surveillance, wiretapping, intimidation, harassment and threats. It’s like the old KGB that comes for you in the dark of the night, banging through your door.”

This is special counsel Robert Mueller’s investigation of Russian interference in the 2016 presidential election, as seen through the eyes of news anchor and analyst Gregg Jarrett this week. Anyone expecting him to be challenged live on air was destined for disappointment.

Fox News host Sean Hannity replied: “This is not hyperbole you are using here.”

It was one telling glimpse of the parallel universe that Donald Trump hopes will save him from Mueller’s sprawling investigation and potential impeachment. Far from an outlier, it was typical of how in recent days rightwing media, congressional Republicans and Trump’s base have gone to war, seeking to discredit and delegitimise the special counsel.

Profile Who is Robert Mueller? Show Background Robert S Mueller III, 74, is a former FBI director who was appointed by George W Bush and held over by Barack Obama beyond his 10-year term. The term extension required special congressional action which the Senate approved 100-0. Previously, Mueller held two different US attorney posts and was an assistant attorney general in the George HW Bush administration.

Special counsel Mueller was appointed special counsel in May 2017, eight days after Trump fired FBI director James Comey. A special counsel is a prosecutor appointed in extraordinary circumstances or in cases of conflicts of interest within the justice department. In this case, there was a need for someone to investigate the Russian matter who was not appointed by or beholden to Trump. Mueller’s team of 17 lawyers operates independently of, but (ideally) in cooperation with, Congress, which has three committees conducting investigations in parallel to Mueller. Mueller is expected to submit a report to Congress and may bring criminal charges separately. Mueller has a sizeable budget and an open-ended term. He is specifically authorized to investigate “any links and/or coordination between the Russian government and individuals associated with the campaign of President Donald Trump” plus any matters that “may arise directly from the investigation”. He has the power to prosecute federal crimes. Can he be replaced? In theory, William Barr, the new attorney general, could fire Mueller. Barr, who once criticised Mueller's case as “fatally misconceived”, was asked during his confirmation hearing if he would fire the special counsel without good cause and replied: "I would not carry out that instruction." Although, if Trump wanted to fire Mueller, and Barr was unwilling, Trump could replace Barr. Trump's view Trump has said Mueller “is very, very good friends with [James] Comey, which is very bothersome” but also said “Robert Mueller is an honorable man.” Photograph: Saul Loeb/AFP

Even if they do not win in the court of public opinion, they hope to sow enough doubt that should Mueller produce damning evidence of collusion between the Trump campaign and Russia, the reaction will be as divided as everything else in split-screen America, offering the president an escape route.

“It’s the only way he’s going to get out of this: by trying to make the investigation seem partisan,” said Max Bergmann, a senior fellow at the Center for American Progress (CAP) Action Fund in Washington. “It’s the only strategy now: make sure his base is with him and Republicans in Congress won’t hold him accountable.”

Only 56% of Americans are ‘very or somewhat confident’ that Mueller will conduct his investigation fairly, according to a survey of 1,503 by the Pew Research Center. More than two in three Democrats (68%) say they are at least ‘somewhat confident’ that Mueller’s investigation will be conducted fairly. Less than one in two Republicans (44%) think the same way.

There was little doubting the mood among Trump’s core support at a rally in Pensacola, Florida on Friday night. Mike Newell, dressed in gear proclaiming that he was a marines veteran, dismissed the investigation as “a big joke”, adding that it was “all politically motivated and … a shame we’re wasting that kind of taxpayer money on something that’s so ridiculous”.

Newell said he followed the story “all over the media, the fake media mostly” and that the most reliable source was Fox News, which Trump consumes voraciously. “They are accurate on what they say,” he said.

La-Vonne Haven of Pensacola, who was wearing a “Make American Great Again” wool hat to keep warm on an unseasonably cold day on the Gulf coast, said: “We watch Fox when we want to get the truth. I’ll go to Fox because there’s just too much political untruths out there.”

Trump supporters at the rally in Pensacola. Photograph: Nicholas Kamm/AFP/Getty Images

She agreed with Newell that the Mueller investigation should be wound up. “It’s time we put it to rest because there’s nothing against our president.” She conceded that there may be a case against others in the campaign but was confident that Trump was not involved.

Some believe they discern a political plot to undermine the White House. Kelly Moffitt, of Cottonwood, Arizona, said of Mueller’s investigators it “seems they have already drifted and his team is more than just partisan – they have some sort of axe to grind”.

‘They can’t beat us at the voting booths’

Mueller was appointed special counsel in May, following Trump’s dismissal of FBI director James Comey. On the day it emerged Mueller had convened a grand jury, Trump laid out a blueprint for delegitimising the entire exercise, portraying it as a Democratic plot against his supporters.

“They can’t beat us at the voting booths so they’re trying to cheat you out of the future and the future that you want,” he told a rally in Huntington, West Virginia in August. “They’re trying to cheat you out of the leadership that you want with a fake story that is demeaning to all of us and most importantly demeaning to our country and demeaning to our constitution.”

Since October, Mueller has charged four people from Trump’s inner circle, most recently his former national security adviser Michael Flynn. Although the president has avoided attacking Mueller directly, probably on legal advice, he did tweet last week that the FBI’s reputation was in “tatters” while his allies have launched a massive counter-offensive on multiple fronts.

Timeline The key events in the Trump-Russia investigation Show GCHQ warns US intelligence Britain’s spy agency GCHQ becomes aware of suspicious “interactions” between people with Trump ties and Russian intelligence operatives. In late 2015, GCHQ warns US intelligence. Hacking and 'influence campaign' The first phishing emails begin to hit Democratic individuals (the Democratic National Committee having been hacked months earlier). Hundreds or thousands of impostor accounts appear on Facebook, Twitter and other social media.

Trump foreign policy meeting Trump is told about the Russian contacts of at least one aide, and Jeff Sessions shoots down a possible Trump-Putin meeting, according to multiple people present. Later Trump and Sessions repeatedly deny there had ever been such contacts by anyone in the campaign with Russian operatives.

Trump tower meeting Top Trump campaign advisers including Donald Trump Jr meet at Trump Tower with Russian operatives, having been promised "official documents and information that would incriminate Hillary." A Russian present says sanctions were discussed. Republican national convention The convention convenes in Cleveland, Ohio. Russian ambassador Sergey Kislyak attends. Top Trump campaign aides vociferously deny contacts with Russian operatives. WikiLeaks releases 44,000 emails from the Democratic National Committee.

Publication of emails Across the Fall, outlets including WikiLeaks, Guccifer 2.0 and DCLeaks publish tens of thousands of emails stolen from Democrats and the Hillary Clinton campaign.

The Facebook campaign As Russian impostor accounts spread divisive propaganda throughout social media over the Fall, the Trump campaign experiments aggressively with micro-targeting on Facebook, making on an "average day" 50,000-60,000 ads, according to former digital director Brad Parscale

Contacts and denials Top Trump campaign aides Michael Flynn, Jared Kushner and others have dozens of contacts with Russian operatives that are repeatedly denied in public across the Fall. "It never happened," a campaign spokeswoman said two days after the election. “There was no communication between the campaign and any foreign entity during the campaign."

Trump elected Donald Trump is elected president of the United States.

- Presidential transition Trump aides keep up contacts with Russian operatives on matters of policy and appear to hide those conversations from the US government and public. Michael Flynn lied to the FBI about the conversations, then later admitted that Jared Kushner had directed him to seek certain policy commitments from the Russian ambassador.

James Comey fired Trump fires the FBI director. “When I decided to just do it, I said to myself, I said 'you know, this Russia thing with Trump and Russia is a made-up story'," Trump tells an interviewer two days later.

At a press conference on Capitol Hill on Wednesday, Congressman Matt Gaetz said Republicans intend to investigate the “unprecedented bias against President Trump that exists when we allow people who hate the president to participate in the investigations against him”.

He added: “A witch hunt continues against the president with tremendous bias, no purpose and no end in sight.”

A day later Bob Goodlatte, the Republican chair of the House judiciary committee, assailed the FBI over how it handled an investigation into Hillary Clinton’s use of a private email server while she was secretary of state and whether it gave her preferential treatment over Trump.

Republicans also questioned whether Mueller’s team has political bias after media reports said an FBI agent, Peter Strzok, was removed from the Russia investigation because he had traded text messages that denigrated Trump and praised Clinton. The conservative group Judicial Watch is suing to obtain the messages sent by Strzok, who was also involved in the Clinton email investigation.

Chuck Grassley, chairman of the Senate judiciary committee, wrote to the justice department: “Strzok’s behavior and involvement in these two politically sensitive cases raises new concerns of inappropriate political influence in the work of the FBI.”

Such efforts are ably supported by a rightwing media working overtime to chip away at Mueller’s reputation, even at the risk of damaging once sacred institutions. Brian Stelter, senior media correspondent of CNN, wrote this week: “The overarching message from Fox & Friends and Hannity is unmistakable: Mr President, you’re the victim of a ‘deep state’ plot to take you down. Don’t let it happen.”

He added: “It’s an alternate universe. It’s as simple as that. All the hours dedicated to attacking Mueller mean Fox viewers aren’t hearing about the newest developments in the Russia interference investigations.”

Among the examples cited by Stelter were White House press secretary Sarah Sanders’ father, former Arkansas governor Mike Huckabee, who told Monday’s Fox & Friends: “There needs to be an investigation of the investigation.” Another was Lou Dobbs on Fox Business, who said Mueller, Strzok and Comey “should be the subjects of criminal investigations and held fully accountable for crimes against a sitting president and the voters who supported him”.

Hannity, who is close to Trump and whose show enjoys the highest ratings, said in a polemical monologue: “Let’s start off with the head of the snake. Mueller’s credibility is in the gutter tonight with these new discoveries, his conflicts of interests, his clear bias, the corruption are on full display. Mueller is frankly a disgrace to the American justice system and has put the country now on the brink of becoming a banana republic.”

Michael Flynn arrives at federal court to plead guilty to lying to the FBI. Photograph: Jonathan Ernst/Reuters

Stelter also noted the dramatic u-turn by Newt Gingrich, a Trump cheerleader and former House speaker who once described Mueller as a “superb choice to be special counsel” and said “his reputation is impeccable for honesty and integrity”. On Wednesday, Gingrich opined: “Mueller is corrupt. The senior FBI is corrupt. The system is corrupt.”

Other media outlets, including the Wall Street Journal and Breitbart News, have joined in the Mueller-bashing. Joel Pollak, senior editor-at-large of Breitbart, contends the investigation is an attempt to undermine the legitimacy of last year’s presidential election.

“There are some conflicts of interest that are very unusual,” he said in an interview. “The deputy attorney general Rod Rosenstein, for example, is both a witness in the investigation and is overseeing the investigation.”

Mueller has far exceeded his mandate by digging into Trump’s financial records and details about who drafted particular media statements, Pollak believes.

“There is a lot of frustration that much of what the investigation is doing has nothing to do with Russia. At the moment it looks like a political witch hunt, in the way President Trump has framed it. Certainly the Democrats are making no secret of using it for moving towards impeachment. They’ve been trying to do that for a long time.”

But there is nothing that warrants impeachment, according to Pollak. “If Mueller merely says there was an attempt to collude, I don’t think the president’s supporters would abandon him. They would defend him. If Mueller says we think there was actual collusion, it depends what that collusion was. There’s no statutory crime of collusion and I think Trump supporters would defend him. I would.

“If they can find an actual crime, I think people will say it’s time to reckon with this. If it’s something minor, like a mistake on a tax return in 2006 or something, that is not grounds for impeachment. Even if Trump did something illegal during the campaign, I think you’d find his supporters – including me – would say that is not grounds for impeachment because it was the campaign, not when he is president.”

‘The distraction machine’

Bergmann of the CAP Action Fund is confident Mueller will produce evidence of vast collusion and urges Democrats to press the issue with voters in 2018.

“There’s no doubt there’s a concerted Republican strategy to try to discredit the Mueller investigation, throw sand in the eyes of the public and the press and bring up all sorts of ancillary issues,” he said. “When the heat gets turned up, the distraction machine kicks into gear on the Republican side.”

This has ranged from a hunt for leakers, to a row over “unmasking”, to claims that Comey was politically biased, to a faux scandal over a uranium deal involving Clinton and Russia “trying to provide a Russia whataboutism,” Bergmann said.

“Now we’re seeing an effort to say: ‘Oh my God, there was a Democrat in the FBI’, to try to say it’s all biased when Robert Mueller himself is a registered Republican, appointed by George W Bush, who served in Vietnam.”

All of it could save Trump’s skin, Bergmann said.

Quick Guide What are the allegations in the Trump-Russia investigation? Show What are the most serious allegations? The investigation into Trump and his team appears to encompass allegations of collusion, obstruction of justice, abuse of power and charges specific to Trump aides and former aides. Any case along these lines against the president would be historic. Both of the presidents to face impeachment proceedings in the past century, Bill Clinton and Richard Nixon, faced obstruction of justice and abuse of power charges. Is there anything we don't know? It's important to note that the work of the special counsel is secret, and the public has no way of knowing for certain what charges prosecutors may be weighing against the Trump team or, in what would be an extraordinary development, against the president himself. What can the special counsel investigate? Mueller is authorized to investigate "any links and/or coordination between the Russian government and individuals associated with the campaign of President Donald Trump" and related matters. In other words, potential collusion during the 2016 election. But so-called “collusion” is only part of it. The special counsel has the broad authority to build a prosecution wherever the inquiry may lead. The investigation has already resulted in charges against former Trump aides such as tax fraud that do not relate directly to election activity. Anything else? In the course of the investigation, Trump's past business practices have also come under scrutiny. With his first indictments of people in Trump's orbit, the special counsel has demonstrated an appetite for the prosecution of alleged white-collar crimes. The president has denied all wrongdoing. Photograph: Charles Dharapak/AP

“Should the Mueller investigation find evidence of collusion or other crimes, it’s going to be the Republicans who are going to have to make a decision on impeachment. Fox, which has effectively been a state news network, is cementing the base that will stay with Trump. If the base holds, it’s going to be very hard for Republicans to jump ship.”

Matthew Miller, a partner at strategic advisory firm Vianovo and former justice department spokesman, agreed.

“The president has been trying to delegitimise the justice department going back to the summer,” he said. “In the last couple of months we’ve seen the rest of the Republican party join in and follow his lead.

“There have been two goals. First, to kick up dust so there is something else to talk about when the president is under scrutiny. Second, to delegitimise the Mueller investigation so the president can fire him or Congress can ignore his conclusions if he finds Trump broke the law.”

Mueller still has the public’s trust “but I’m not sure that matters to Republicans in Congress”, Miller said. “They’re more and more not accountable to public opinion. If you live in a gerrymandered district where your biggest concern is a primary challenger, you’re no longer concerned about what other people think.”

Donald Trump with his son-in-law Jared Kushner. Photograph: Michael Reynolds/EPA

Trump may consider terminating Mueller sooner rather than later, Miller said. “He probably flirted with getting rid of Mueller and I think [his lawyer Ty] Cobb told him: ‘If you just cooperate it will be over by the end of the year.’ But when January rolls around and Bob Mueller is not only not finished but closer to the president than ever before, there’s a very good chance he’ll look at it again.

“Six months ago I thought there would be a bipartisan outcry, but you only have to watch Fox News for five minutes to see the partisan message that Mueller is on some kind of witch hunt. A lot of the Republican members live in an alternative reality where Fox dictates the terms of the debate.

“That seeps in and, if Trump is found to have colluded with Russia, I would not be surprised if Republicans let him get away with it.”

Bill Galston, a former policy adviser to President Bill Clinton, remains hopeful that Mueller’s authority is holding against the onslaught of conspiracy theories and bilious punditry.

“They’re doing their best but so far they haven’t succeeded,” he said. “The data shows there is solid and pretty stable majority support for the Mueller investigation. My bottom line judgment is that his recommendations will be given significant public weight. I think his reputation both precedes him and strengthens him.”

As for Hannity’s diatribe, Galston, a senior fellow in governance studies at the Brookings Institution think tank in Washington, observed dryly: “If you throw that kind of mud into a gale force wind, it’s likely to come back in your face. I’m sure Mr Hannity knows a disgrace when he sees one and that’s in the mirror when he shaves every morning.”