As Speaker, Boehner is the highest elected member of his party; in effect if not title he is the Republican Party leader, at least until a candidate for the presidency is nominated. He is also a man not unknown to express his emotions in public. A fortnight ago Boehner, a Catholic, wept as he welcomed Pope Francis to the chamber to become the first ever pontiff to address a joint sitting of the US Congress, and an hour later he wept again as he escorted the Pope onto the Speaker's Balcony of the Capitol Building to greet the 50,000 well-wishers who had gathered on the National Mall to greet him. The following day he strode into a press conference room in the bowels of the Capitol singing, actually singing, "Zip a doo dah, zip a dee day," and quit his miserable job. Fear and loathing

Boehner ascended to the speakership in 2011. This was just after the 2010 midterm elections, which had resulted in a sweeping success for the Republican Party after it waged an all-out campaign against Barack Obama, and in particular against Obamacare. When the votes were counted the Republican Party held control of both houses of Congress and 31 governorships across the country. It had been a campaign marked by fear and loathing. Obama, it was said at town hall meetings set up by the Tea Party movement (attended by grassroots, but often quietly funded by anti-tax billionaires) across the country, was planning to set up death panels across the country to kill off the elderly. "The GOP has become an insurgent outlier in American politics. It is ideologically extreme; scornful of compromise". The President, it was claimed by elements of this far-right movement, was variously a communist, an anti-colonialist Kenyan, a Muslim Manchurian candidate. (Indeed 43 per cent of Republicans still believe Obama is a Muslim.)

Looking back on how such nonsense took hold in the mindset of a major party, people point to different causes. Some blame Fox News, which championed the Tea Party and gave voice to fringe elements. Some blame racism. Others point to fears stoked by the crippling recession that threatened to wipe out the livelihoods of a generation of working and middle-class Americans, particularly those of the manufacturing belt that had created the American century. The same people felt threatened by rapidly changing demographics and mass immigration. There is doubtless truth to all these explanations, but it is probably worth noting that mistrust of established politics and rising extremism has been a phenomenon experienced not just in America, but in Europe and to an extent in Australia. In any event, the effect on Congress was immediate and profound.

The incoming class of Republican congressmen and women in 2010 contained a hard-core minority that had campaigned not just on defeating Obama, but on defeating Washington itself. The GOP establishment soon found the hardliners were utterly unmanageable, and that their demands were often radical enough that they threatened to do damage not only to the President's agenda, but the Republican Party, and the very institution of Congress. They sought not to govern, not even to oppose, but to wreck, to literally diminish the government and prevent it from going about its business. They were and are loyal to the Republican Party only to the extent that they can harness the party to achieve these goals. At first the gulf between the anti-government Tea Party and the small-government Republican establishment did not seem to be too great.

This was because the establishment had already embarked on a policy of total obstruction to all Obama initiatives. This strategy, which breaks with the modern American tradition, was settled upon at a meeting in a DC steakhouse called the Caucus Room held by the Republican strategist Frank Luntz and attended by GOP congressional leaders on the very day of Obama's inauguration. Those in attendance – including former speaker Newt Gingrich and future Mitt Romney running mate Paul Ryan – had just seen a crowd of a million people cheer on the National Mall as Obama swore his oath of office. The sight had horrified them. Obama, they decided, presented an existential threat to the GOP, and he needed not only to be blocked, but discredited. So at first the coalition between the Tea Party and the Republican establishment worked together in blocking the White House agenda. The cracks started to show in 2011 when the Tea Party freshmen embarked on a strategy of hostage-taking.

Unless Obama agreed to their demands for tax cuts, the GOP would refuse to pass authority needed to allow the administration to pay the nation's debts. Plunging into default would be catastrophic, potentially putting the nation and the world back into the pits of the great recession they had not yet recovered from. Just the threat of it was enough to prompt Standard & Poor's to strip America of its AAA rating for the first time. "The downgrade reflects our view that the effectiveness, stability, and predictability of American policymaking and political institutions have weakened at a time of ongoing fiscal and economic challenges," the agency observed at the time. Obama made concessions, and the debts were paid, but Obama vowed he would never again give in to a group that he said would take the nation's economy hostage for their political gain.

And he never did, but the Tea Party never gave up on the tactic. In 2013 it coerced Boehner into threatening to block monetary supply unless Obama repealed his signature healthcare reform. Obama refused and the government shutdown for 15 days in October, costing about $24 billion or, according to Standard & Poor's, 0.6 per cent of annualised fourth-quarter 2013 GDP growth. The majority of the public rightly blamed the Republican Party. A government employee protests over the shutdown at the US Capitol in 2013. Credit:Karen BLEIER This year the Tea Party right, now organised as the "Freedom Caucus", is demanding that the Republican leaders shut down the government unless Obama pulls $US500 million federal government funding from Planned Parenthood, the reproductive health, non-profit organisation that provides healthcare – including abortions – to poor women across the country.

Boehner has refused, not because he has any love for Planned Parenthood – he is a pro-life Catholic – but because he knows the tactic will not work. He knows Obama will refuse, the government will shut down, the public will blame Republicans. Two of the most respected scholars of Congress in Washington, DC, are Thomas Mann, of the Brookings Institution, and Norm Ornstein, of the American Enterprise Institute. Writing in The Washington Post about a Congress that not only does nothing, but also tries to prevent anyone else from governing, Mann and Ornstein were unsparing: "We have been studying Washington politics and Congress for more than 40 years, and never have we seen them this dysfunctional. In our past writings, we have criticised both parties when we believed it was warranted. Today, however, we have no choice but to acknowledge that the core of the problem lies with the Republican Party. "The GOP has become an insurgent outlier in American politics. It is ideologically extreme; scornful of compromise; unmoved by conventional understanding of facts, evidence and science; and dismissive of the legitimacy of its political opposition." Some time this year, Boehner decided he had had enough. Though he was as conservative a man as had occupied his position in a generation or more, he spent his weeks being white-anted and heckled by Tea Party elements of his own party as a RINO (Republican In Name Only) and his weekends travelling the country raising funds for them.

So after he met the Pope, Boehner announced his resignation – while singing - and the Freedom Caucus cheered another success. Then, on Thursday, Republican members gathered to elect a new leader, and it was universally accepted that Kevin McCarthy, a man to the right of Boehner, would walk into the job. Instead, he pulled his candidacy in the very meeting that was expected to elect him. There are two competing rumours about his resignation – one, that right-wing Republican elements planned to spread rumours that he had had an affair, and another that he had refused to bow to Tea Party demands that he again force a shutdown. House Majority Leader Kevin McCarthy, a Republican from California, pulls out of the race for Speaker. Credit:Drew Angerer The chaos within the Republican Party in Congress is being amplified outside it.

With America congressional districts so effectively gerrymandered, Republican members and candidates no longer fear attack from the Democratic left, but from the Republican right. This has led to the party becoming increasingly divorced from mainstream politics. Views that once would have been considered radical are now orthodox in the GOP, and the new orthodoxy has taken hold in the presidential primaries, which have so far been dominated by Tea Party-style outsiders – people like Donald Trump and Ben Carson. Trump made his name in the Tea Party movement as a champion of the "birther movement", claiming that Obama was ineligible to serve as president because he was not a true American citizen. He has leveraged this into a presidential campaign built on a platform founded on three preposterous promises – that he can wall off Mexico, that he can make Mexico pay for that wall, and that the US can round up an estimated 12 million undocumented immigrants, detain them and then remove them.

Carson, who trails Trump, has made his political impact in the party not so much with preposterous promises but with preposterous statements: Obamacare is worse than slavery, the Holocaust was exacerbated by gun control, evolution is a fairytale. Next in the polls comes Carly Fiorina, the former Hewlett-Packard chief executive, who leapt in the polling by reiterating false claims made about Planned Parenthood by a pro-life group. They claim to have video evidence that Planned Parenthood profits by selling the body parts of babies born alive and then murdered. The claims have been dismissed as untrue by every fact-checking organisation that has waded through the hours of tape they have provided. Carly Fiorina, former chairman and CEO of Hewlett-Packard, and 2016 Republican presidential candidate. Credit:Daniel Acker Fiorina is unbowed by this evidence, and in this post-modern primary campaign she is being well rewarded for her dogged insistence that fiction is fact.

These three are being trailed by establishment candidates like Jeb Bush and Marco Rubio. But even these two have bowed to the new orthodoxy. Bush, son and brother of a president, insists he is a DC outsider, and like Rubio he rails against abortion and denies climate science. Both have backed away from previous commitments to reform the immigration system, both have advocated tax cuts as the best means to address deficits, a policy dismissed by the non-partisan Congressional Budget Office and described by Bush's father, George H. W. Bush, as "voodoo economics". Also in the mix is senator Ted Cruz, a Tea Party champion whose strategy so far consists of appeasing Trump supporters in the hope he can scoop them up should Trump implode. Cruz has gone so far in this effort as to endorse the conspiracy theory that swept the Republican right this year that under the guise of military exercises known as "Jade Helm", Obama planned to use US Special Forces to invade Texas and imprison dissidents in Walmart outlets.

Cruz said the theory was worthy more study. "My office has reached out to the Pentagon to inquire about this exercise," he told Bloomberg. So far most observers still predict the insurgent campaigns will fade out over the northern autumn and winter and candidates like Bush and Rubio will come to the fore. But it is unclear how much damage they will have done to the Republican brand in pandering to fringe elements to survive. And in Congress itself the Freedom Caucus remains utterly unrepentant. Asked what the renegades wanted to support a candidate for the Speaker's chair, Dave Brat, the Virginian who took down former House majority leader Eric Cantor in 2014, said: "We want rules, policy, process. We want that on paper ahead of time." That is to say, they want the lot – they want total control of the House Republican Party.

After Thursday's blunder a movement was launched to conscript Ryan, the fiscal hawk, as a compromise candidate who was thought to hold universal regard. Even as he said he didn't want the job, a far-right movement against him was formed. Hours after he announced his withdrawal from the race for the Speaker's chair McCarthy was asked by the conservative National Review if the House Republicans were ungovernable. "I don't know," he said. "Sometimes you have to hit rock bottom." He was not alone in his dismal outlook. "It is total confusion – a banana republic," the New York Republican Peter King told The Washington Post. "Any plan, anything you anticipate, who knows what'll happen. People are crying. They don't have any idea how this will unfold at all."

And so the Republican Party is heading into the election year split and, so far, leaderless, while the Tea Party cheers at its success at destroying the leaders of the party it occupied as a host organism in 2010. Boehner has agreed to stay on as Speaker until the mess is sorted out. After he quit, but before he later agreed to hold on, he told colleagues: "I had this terrible nightmare last night that I was trying to get out and I couldn't get out. And a hand came reaching, pulling me."