If you hang around Los Angeles for a day to two you will see enough strange things to fill a respectable screenplay.

The biggest news this week was the surprise comeback of Britney Spears, who returned to touring after a three-year break. She showed up unannounced at the House of Blues in Anaheim, clad in a brunette wig, knee-high go-go boots and a fur coat that revealed glimpses of a jewel-encrusted bra.

Lip-synching her way through the full repertoire of Spears classics, she won rave reviews from her neglected fans. “She looked so freaking hot,” Julie West, 16, told the Los Angeles Times.

But if you think that odd, consider this. Ten Republican presidential hopefuls gathered here last night to make their case that they should be the next US president. Though no-one showed up in a jewel-encrusted bra (Rudolph Giuliani presumably resisting what must have been a powerful temptation), the event was still an unusual spectacle in this part of Southern California.

Los Angeles is hostile territory for Republicans. The city’s entertainment elite is committed to the belief that conservatives are so evil that they should only ever be portrayed in adult films and played by Manichean-looking British actors.

Republicans have also alienated the city’s massive Latino population – once thought of as potentially solid Republican voters – with a nativist message on immigration.

So what were these Republican hopefuls doing here, or more accurately, just outside the metropolis in the lumpy scrubland of the Simi Valley? The answer is Ronald Reagan.

The candidates had been invited by Nancy Reagan to the Reagan Presidential Library. The event was a useful reminder of the power the Reagan legacy has over Republicans. Margaret Thatcher, Mr Reagan’s partner in the 1980s, is now seen as something of a liability by her party. There are a few Republican intellectuals who would like American conservatives to follow suit and tone down some of the Reagan-worship. Some think the roots of today’s conservative crisis actually go back to Mr Reagan and his simple embrace of free markets and assertive American idealism.

Even some of those who admired the former president think he is simply no longer relevant – that the Reagan message of smaller government and firm resolve against global ideological enemies is just not suited to the modern challenges of rising economic insecurity and the diverse and complex threat from Islamic radicalism.

That the world is a different place from 25 years ago ought not to be in dispute. But it seems to me that the problem with the Republican Party in the past five years is not that it has tried unsuccessfully to apply the Reagan principles to modern times, but that they have misappropriated the Reagan legacy for their own ill-advised and indefensible objectives.

The Reagan imprimatur has been rolled out and sent into service in defence of things the great man would find incomprehensible. He stood for less government, for a start, but Republicans have joyfully expanded the size and scope of government, while ignoring a looming fiscal catastrophe from an ageing population.

Mr Reagan cut taxes from absurdly high levels to regenerate American enterprise. This successful approach has turned over the years into a calcified dogma that says no Republican can challenge the contention that taxes should be cut all the time and as often as possible, whatever the economic circumstances, on the alchemist’s proposition that such cuts will always and everywhere “pay for themselves” in increased government revenues.

In foreign policy, Mr Reagan’s legacy has also been traduced by his would-be successors. He did indeed challenge the prevailing diplomatic assumptions and directly took on the enemies of freedom in the world. But he never shrank from making uncomfortable compromises with reality. So distorted has US foreign policy discussion on the Right become that some of the things Mr Reagan did would probably provoke cries of appeasement if they were done today. In 1983, for example, after 200 US Marines were murdered by a suicide truck bomber in Lebanon, Mr Reagan immediately pulled all US forces out of the country.

My favourite story about him concerns the US invasion of Grenada, just after that infamous Beirut incident in 1983. It illustrates the kind of wisdom that has been sorely lacking in the Bush Administration’s foreign policy in the last five years.

The President was being briefed on the invasion plans by his senior military officers just before the Grenada operation. As was often the case, Mr Reagan did not seem to be paying close attention, according to one of those present. But when the briefing was over he had one question. He wanted to hear again the number of troops the planners were going to send in. He was told a figure and shook his head. “Make it twice that,” he told a slightly puzzled general. Asked why, the President said calmly: “If Jimmy Carter had sent 16 helicopters rather than eight to Desert One to rescue the US hostages in Iran in 1980, you’d be sitting here briefing him today, not me.” Grenada was not Iraq, but just as assuredly George W. Bush is no Ronald Reagan.

What may be most relevant about Reagan is this: he became President in the midst of one of those periodic crises of American self-confidence, in which the nation’s spirit had been sapped by a disastrous war, a series of scandals that undermined confidence in government and the failures of a comically inept Administration.

Within a few years the President had led the American people back to an improbable victory in the Cold War and an unchallenged status as the world’s economic superpower. America needs that leadership again.

Times Recommends

• It’s the beginning of the affair
• Afghanistan: still a price worth paying
• Heroes of the downtrodden