Donald Trump's presidency following the dismissal of Steve Bannon, an editor at far-right outlet Breitbart has said.
Joel Pollak, a senior editor at large at Breitbart News predicts Mr Trump's presidency will lose direction and the backing of his supporters after the firing of the far-right figurehead in the White House.
Mr Pollak, who said his publication will be going to "war" with the White House following the announcement of Mr Bannon's departure, warned that unless the US President upheld his campaign pledges that were so vigorously defended by his chief strategist, "his presidency will be a failure".
Speaking to Radio 4's Today programme, Mr Pollak said: "If Trump veers away from the agenda that he campaigned on and the white board of promises that was hanging in Steve Bannon's office then he will lose his base and he wil lose his direction and his presidency will be a failure.
"If Trump sticks to what he promised then yes he will deserve credit for fulfilling the hopes of his voters but people looking at other people that Trump brought into the administration....... Trump supporters would be looking at some of these appointments and wondering if these personnel would dictate future policy. In that confusion and doubt, Bannon was a reinsurance."
The Breitbart editor added that as long as Mr Bannon was in the White House, supporters of the Trump administration did not have to worry about "some of these other opponents".
Mr Pollak referred to White House advisors including Mr Trump's daughter Ivanka Trump and his son-in-law Jared Kushner, who he described as "somewhat conservative" but whose "political persuasions remained unknown".
Mr Bannon epitomised President Trump's anti-globalist "America First" agenda and he reportedly clashed with the President's son-in-law, who has been seen as adopting a so-called globalist approach to the US's role on the world stage.
For Breitbart News, Mr Bannon's departure represents a significant shift of power away from the anti-globalist agenda.
Throughout the interview, Mr Pollak repeatedly compared Mr Trump to Arnold Scharzenegger, the actor and former professional body-builder who was elected as a Republican governor in California.
He claimed Mr Scharzenegger had been elected on a platform of radical reforms but that "at the first signs of difficulty" he switched his political fortune to become "a very liberal governor, basically a democrat".
Mr Pollak admitted Mr Scharzenegger was re-elected following his change of direction but claimed this led to the destruction of his political party in California and warned Mr Trump could be heading towards a "Scharzenegger 2.0".
"It may boost his [Mr Trump] reelection chances, although I doubt it, but I think it will ultimately disappoint his base and it will abandon the mission for which he was elected 'to drain the swamp' as he put it," Mr Pollak added.
Now that Mr Bannon has left, the far-right nationalist seen as one of the most influential figures in the White House will return to Breitbart News as an executive chairman.
Explaining his tweet "#WAR", Mr Pollak said it had been the motto of Breitbart News since the website's foundation.
"It indicates to our readers that we are going to continue our relentless editorial push against the Hollywood cultural elite, against the Democratic establishment and the institutional left and against the Republican establishment inside the Beltway," he said.
Mr Bannon joined the Trump presidential campaign a year ago and remained in his post as White House advisor for seven contentious months.
He was seen as one of the main drivers of the Trump administration's populist agenda including the decision to leave the Paris Agreement and the repeated attacks on "fake news media".
Mr Bannon was an architect of Mr Trump's election victory and Mr Pollak claimed he was hired by the campaign team at a time when it "was expected to go down as a crashing defeat, bringing the rest of the party with him".
After Mr Trump's "improbable victory", Mr Pollak said Mr Bannon was "in the unique position to bring ideological focus to the Trump administration and he represented the thoughts and the wishes of the voter base" because of the overlap between Trump supporters and Breitbart News' audience.