The witches cauldron of bile and vitriol that has been set simmering at the Republican Convention heralds a campaign for president more toxic than any in modern political history.

While the first two days of the gathering of the Republican faithful – or rather the Donald Trump faithful – have seen barely a scintilla of discussion of actual policy, the energy in the Quicken Loans Arena, such as it is, has been directed almost exclusively at tearing down Hillary Clinton.

If demonising the opponent is regular grist before a presidential contest at national conventions, the sheer ferocity of the attacks against the assumed Democratic nominee – she will be acclaimed at her own convention in Philadelphia next week – is proving unprecedented.

As Chris Christie, the Governor of New Jersey, used his past credentials as a prosecutor in his state to recite a list of alleged misdeeds by the former secretary of state, including her misuse of a personal email server while she was in that office, he concluded each point by asking the room if she was “guilty or not guilty”, evoking an image almost of a public guillotining.

‘Every region of the world has been infected with Hillary Clinton's flawed judgement’, Chris Christie told Republican delegates in Cleveland (Getty) ((Getty Images))

And he seemed, from where The Independent was sitting, to be rolling his tongue in his mouth in delight as large sections of the room bellowed back each time, “lock her up! Lock her up”. He must have known what the effect of his words would have and how the room would respond.

Few moments were more striking, however, than the stepping onto the convention stage earlier of Pastor Mark Burns, whose job only was to lead the assembled delegates in a brief prayer, a ritual for both parties at their gatherings asking for reflection on faith – not on political warfare.

But war was what Pastor Burns, who preaches the so-called “prosperity Gospel” in South Carolina, had in mind as he asked God to help defeat Ms Clinton, the “enemy”.

“I’m going to pray and I’m going to give the benediction,” he began. “And you know why? Because we are electing a man in Donald Trump who believes in the name of Jesus Christ. And Republicans, we got to be united because our enemy is not other Republicans – but is Hillary Clinton and the Democratic Party.”

His attempt to recruit God to the cause shocked some. “I have rarely heard a more inappropriate contribution to political proceedings,” Interfaith Alliance President Rabbi Jack Moline told ThinkProgress. “The idea that a member of the clergy would invoke his God’s name and, in the next breath, declare the candidate from the other party to be the enemy seems to be an attempt to replace ‘nomination’ with ‘ordination’.”

By Wednesday, the Trump campaign manager, Peter Manafort, was trying to push back against any impression that the convention has dissolved into a toxic festival of anger and disgust.

“The tone of the convention is multiple tones,” he said. “There is anger among the delegates, but that is out there in America where people are feeling frustrated by failed leadership, by difficult economic times. But that’s not the tone of the convention, that may be an undertow.”

But undertow is hardly a sufficient description of the repeated eruptions of anti-Hillary poison. When retired General Michael Flynn, a former director of National Defence Intelligence for President Barack Obama, provoked calls of “lock her up!” during his speech on Monday, he looked down at the floor and intoned, “you’re damn right. There's nothing wrong with that.”

A mother of one of the US servicemen killed in the attack in Benghazi on 2012, almost went as far as to say Ms Clinton had murdered him. “I blame Hillary Clinton personally for the death of my son, personally,” Pat Smith said.

Locking her up would be one thing. But a veterans affairs advisor to Mr Trump told an interviewer meanwhile that because of Benghazi, he would recommend a different fate. “This whole thing disgusts me, Hillary Clinton should be put in the firing line and shot for treason," said Al Baldasaro, who is also a member of the New Hampshire delegation to the convention.

A sign against the Democratic presidential candidate Hillary Clinton is held aloft at the Republican convention yesterday (Getty)

In 1992, Pat Buchanan, after dropping his own nomination bid, told the Republican convention in Houston that a “culture war” had been set off by Bill Clinton, the Democratic nominee, and called him a Vietnam draft-dodger and railed against the “raw sewage of pornography that pollutes our popular culture”. The right-wing fringe of the party loved him for his boldness.

But when a US Senate candidate from Colorado, Darryl Glenn, lit into Ms Clinton in Cleveland and delivered the line ,“she loves her pantsuits, but we should send her an email and tell her she deserves a bright orange jumpsuit” – orange is the colour worn by most women prison inmates – it was the whole arena that roared its approval. The fringe has become the whole.

And it was the whole that ignited when Ben Carson, the ex-brain surgeon and one-time rival of Mr Trump for the nomination, appeared to draw a line between Ms Clinton and Lucifer.

It remains to be seen whether in their inevitable assailing of Mr Trump next week in Philadelphia the Democrats similarly allow themselves off the chain and into the underbrush of character assassination. If they do, they might stop at suggesting he belongs in prison.

The risk for the Republicans meanwhile is clear. Mr Manafort spoke of the “joy” he had seen on Tuesday night among delegates after the formal nomination of Mr Trump and his running mate Governor Mike Pence. And he attempted to underline the testimonials given about the sweet and loving nature of their father by two of the candidate’s children, Donald Jr and Tiffany.

But that alleged joy is not what lingered after the Arena emptied. What lingered was “lock her up!” The effect, surely, was to swamp any attempt the party is making to soften the edges of the caricature image of Mr Trump and thus make it harder to broaden his base of appeal.

You have to wonder. One of Mr Trump’s biggest challenges is making himself more likeable to women. How will the vision of Mr Christie leading an effective mass, if rhetorical, lynching of Ms Clinton, who is on the brink of a historic bid to become the first female president, help with that?

And how can we expect anything between now and 8 November that might resemble even slightly a campaign of ideas and policy prescriptions, let alone one of hope?