Donald Trump's one-time Republican presidential rival Jeb Bush warned of a "chaos" Trump presidency. Well, here we are. And when the "chaos" president reigns, the cascade of disorder pours.

Take this past week, which saw:

A jaw-dropping bipartisan roundtable unfold before live TV cameras, during which president Trump endorsed gun-control measures traditionally opposed by Republicans.

Confirmation that one of the president's longest-serving and trusted aides Hope Hicks will resign.

A rare, public clapback from Trump's oft-maligned Attorney General Jeff Sessions.

And a surprise announcement on tariffs that roiled the stock market, prompting Trump to tweet that "trade wars are good."

That's not to mention rumours dogging the White House that Trump is so fed up with his national security adviser H.R. McMaster that he could fire him this month. Or the prospect that Trump's tariffs proposal could push economic adviser Gary Cohn out the door.

(All happening, by the way, against the backdrop of special counsel Robert Mueller's investigation into Russian meddling, a probe that has ensnared Trump associates, who have come under questioning.)

But while the Trump presidency has been through tumultuous periods before, what's notable this time is who he's alienating: The Republicans.

White House Communications Director Hope Hicks, one of President Trump's closest aides and advisers, arrives to meet behind closed doors with the House Intelligence Committee, at the Capitol in Washington on Tuesday. (J. Scott Applewhite/Associated Press)

The Grand Old Party is now being tested on whether it will side with a president who seemed to disagree with long-standing partisan orthodoxy on gun rights and free trade, as well as their political fondness for Sessions as a principled ultra-conservative.

That was some intense shit. I was blackout furious by that. - Gun-rights activist Joe Biggs

In a terse statement, House Speaker Paul Ryan urged Trump to "consider the unintended consequences" of the plan to slap 25 per cent tariffs on steel imports and 10 per cent tariffs on aluminum imports.

Republican senator Ben Sasse of Nebraska slammed the tariffs idea as "bad" policy from a "supposedly Republican" administration.

Even if Trump backpedals next week, the real-world effects have landed. Stocks opened sharply down on Friday, the morning after the tariffs announcement.

"Whoever advised him on this should be reprimanded," Republican senator Orrin Hatch told reporters.

That wouldn't have been Cohn, who previously tried to talk the president out of the protectionist proposal, reasoning it could be economically disastrous. Cohn is reportedly considering quitting.

Flanked by Senators John Cornyn, a Republican from Texas, and Dianne Feinstein, a Democrat from California, U.S. President Donald Trump meets with bipartisan members of Congress to discuss school safety in the wake of the Florida school shootings at the White House in Washington on Wednesday. (Kevin Lamarque/Reuters)

"Maybe he'll leave," said Steve Billet, director of the Masters in Legislative Affairs at George Washington University. "If you're in a position like that in the White House and the president isn't listening to you, your choices are to stick around and continue to offer advice that's ignored, or just leave."

Billet's Republican congressional contacts have expressed concerns with him privately that the party is losing its way, he said.

"Republicans believe the party is moving off an ideology … in a way that would have William Buckley clawing himself out of his grave and searching for Donald Trump's neck to squeeze," Billet said, referring to the late arch-conservative commentator.

Republicans eyeing the polls have reason to fret. Trump still commands the party base, with a Gallup poll showing he enjoyed an 85-per-cent favourability from Republicans in late February.

When a country (USA) is losing many billions of dollars on trade with virtually every country it does business with, trade wars are good, and easy to win. Example, when we are down $100 billion with a certain country and they get cute, don’t trade anymore-we win big. It’s easy! —@realDonaldTrump

"It would be a reasonable conclusion to suggest Donald Trump now owns the Republican party," Billet said. "Or if not, he has it on a long-term lease."

A managerial style rooted in "chaos" has long been the president's modus operandi even since before the campaign, said Bruce Miroff, a professor of political science at the University at Albany.

"Everything is done on the fly," Miroff said.

"But one of the things that's different here now is that he's freaking out his own party more than any moment in the past."

Earlier in the week, Trump boasted that he would take on the National Rifle Association (NRA). And in remarks at a televised bipartisan meeting on Wednesday, he appeared to delight some Democrats in the room when he voiced support for confiscating weapons from some individuals.

"I like taking the guns early…Take the guns first, go through due process second," he said in remarks that infuriated gun-rights advocates.

Joe Biggs, a gun-rights activist and journalist for the right-wing news outlet Liberty One TV, was "blackout furious" following Trump's remarks Wednesday in support of confiscating firearms from certain individuals without due process. (Twitter)

"That was some intense shit. I was blackout furious by that," said Joe Biggs, a Texas-based NRA member who reports for the right-wing outlet Liberty One TV. "From a so-called right-wing president, that was such a stupid thing to say. If he goes through with it, he'll lose all his … base."

In a tweet the next morning, Trump appeared to walk back his comments, saying he had a "great" meeting with the NRA.

Biggs wasn't appeased.

"All I saw was a tweet," he said. "That means nothing until I see him take a stage somewhere and talk about being pro-Second Amendment instead of acting like Stalin."

Reached in New York, former Trump campaign adviser Sam Nunberg, who was fired in 2015 over racially charged remarks on social media, told CBC News that Trump expressed to him that he believes in stronger gun control.

"He's going to pass something. I can tell you that Trump is going to be the one who's going to take on the NRA," Nunberg said Friday.

A 2017 file photo shows former White House staff secretary Rob Porter. The near-constant fixture at President Donald Trump's side resigned from his post last month after two ex-wives publicly accused him of domestic abuse. (Nicholas Kamm/AFP/Getty Images)

"He doesn't believe lunatics should be able to buy guns, doesn't believe 18-year-olds should be able to buy an AK-47."

Nunberg said he and Trump had never discussed his stance on a national ban on assault-style rifles, but he noted that in Trump's 2000 book The America We Deserve, he supported such a ban.

Asked about Trump's leadership style, Nunberg said: "He likes chaos. He likes playing people off of each other."

This week of upheaval follows the departure of top White House aide Rob Porter, following a domestic abuse scandal. That was followed closely by the president's son-in-law Jared Kushner getting stripped of his interim security clearance.

Former Trump campaign adviser Sam Nunberg described Trump's managerial style as "chaos," and said that in his conversations with Trump during the campaign, the president indicated he favoured stronger gun control. (YouTube)

Personnel changes have hollowed out a West Wing once populated by dependable Trump confidants like Porter and Hicks, said Chris Edelson, an expert on presidential powers at American University.

"Trump has had an especially out-of-control week, but chaos has been his life," Edelson said. "We've reached these points before, but it's pushing people too far. Hope Hicks left, so maybe it got to be too much. If she's leaving and she's so close to him, others may feel similarly and follow."

"The thought I've had from the beginning," he added, "Is how long can you keep up this kind of presidency?"