At the Republican national convention, the keynote speaker on its first night delivered a thunderous address. He declared: “This election is about who we are. It is about what we believe and what we stand for as Americans. There is a religious war going on in this country. It is a cultural war, as critical to the kind of nation we shall be as the Cold War itself. For this is the war for the soul of America.”

That speech was in fact delivered 28 years ago at the 1992 convention in Houston, by Pat Buchanan, who had unsuccessfully challenged the incumbent Republican, president George HW Bush, for the party’s nomination. It electrified the party faithful but was thought by many to have painted the party in shades too extreme to defend the challenge of moderate Arkansas governor Bill Clinton.

Acidic columnist Molly Ivins riposted on the Buchanan barn-burner that “the speech probably sounded better in the original German”.

This week, the Republicans “gathered” again, though virtually, to renominate Donald Trump for the presidency, a race the polls suggest that he, like Bush, will lose.

Of the other Bush, George W, who succeeded Clinton as president, there was no sign. He was not invited to the Republican event, and neither were Bob Dole and Mitt Romney. But there were plenty of latter-day Buchanans giving full voice to the vituperation and politics of rage and resentment that have provided Trump with the rocket fuel for his grievance-based presidency. Not least from the “great man” himself, who used his reality show smarts to orchestrate a convention that coronavirus converted into a television-only event.

There is an excellent documentary on Showmax, American Dynasties – The Bush Years, which serves as a reminder how the Trump phenomenon has completely transformed the 166-year-old Grand Old Party (GOP) into more a personality and family cult than one of the longest enduring conservative movements in the world.

Bush snr personified the sort of East Coast country club internationally minded elite that had provided the party with a base and its leaders. But while his outlook was moderate and global, he did not disavow the political hardball play he knew had to be lobbed to get elected: dog-whistle calls on race in his 1988 election with the infamous Willy Horton ad, and in 1992, inspanning Buchanan and his “Make America First Again” trope, plus the cultural wars.

Bush looked at domestic politics as a means of achieving international aims. Now Trump has skewed foreign policy to fit his domestic agenda. Whether he has an agenda beyond his mantra of “winning, I like to win”, is open to doubt.

For the first time in its long and storied history, the GOP has not bothered to provide voters with a platform or manifesto. Instead, this week the party committee charged with this task “enthusiastically supported President Trump’s America First agenda”. This led one respected analyst to ponder “whatever that means beyond a bewildering series of changing impulses and often outright falsehoods”.

If the Bush family ethic involved a principled and even “compassionate” conservatism, the Trump takeover of the party is untethered to core conviction and more driven by momentary needs and personal gratification for the party leader. Where the GOP once attempted to offer a big tent to house its various factions, the Trump version is built of a smaller but more intense base of true believers.

This stratagem worked four years ago – but then Trump had no track record to defend, no coronavirus crisis to confront and faced one of the most divisive Democrats, Hillary Clinton, ever nominated.

It’s hard to paint his opponent this year, Joe Biden, as either mean or corrupt, though plenty of the speakers this year tried their hand at it. And he has a big lead in the states that determine the outcome.

Still, there is one enduring link between the Republican Party of old and the Trump version of today. Both iterations champion law and order, and security.

An analyst once divided the two parties on old parental lines. The Democrats were the “Mommy Party”, strong on social and welfare issues. The Republicans were the “Daddy Party”, tough on discipline and policing.

Of course, the very concept of marriage has been expanded since, and the Buchanan appeal against the “homosexual agenda” has been consigned to history.

But some things still endure. This week’s convention played out against the background of rioting in Wisconsin – a key battleground state – following the Black Lives Matter fracas in Minnesota, another must-win state for incumbent and challenger.

Biden, whose convention pitch last week was bathed in an appeal to “light against darkness”, might find that the ground will start to shift against him if the disorder continues. A strong Daddy could yet beat a softer Mommy.

I recently bet against that outcome, but then I predicted President Hillary Clinton.

Leon, a former leader of the opposition, now chairs Resolve Communications.

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