“When I was a child,” wrote St Paul nearly 2,000 years ago, “I thought as a child: but when I became a man, I put away childish things.” The great apostle could not possibly have counted on the invention of the electric guitar. Since the 1960s this instrument has represented one childish passion that men of all ages show no signs whatever of putting away. We may have grown tired of Tony Blair’s politics, but we still understand why his Fender Stratocaster remains one of his most prized possessions (even if we wince slightly at the thought of him attempting to accompany Robin Gibb in a Bee Gees medley).

The youth of the mid-1990s had their heads turned by the chemical allure of turntables and electronica, but this was just a brief fling. Britpop bought the guitar back into the ascendant and now guitar bands are ubiquitous once more: see the Kooks, the Killers, Arctic Monkeys, Razorlight, the Zutons, Maximo Park, Snow Patrol and the Twang. Nearly half a million electric guitars were sold in Britain last year (a record) and it has become the most-learnt instrument in our schools.

For the baby boomers the love affair has never faded. And for those who always regretted swapping their Rickenbacker for the job in recruitment, or their Telecaster for the lucrative career in television, there is a new opportunity to reacquaint themselves with the thrills of the plectrum and the wah-wah pedal. Later this year the Rock’n’Roll Fantasy Camp opens in Britain. For a mere £9,095, wannabe Pete Townshends can spend six days being tutored by bass legend Jack Bruce, Gary Brooker of Procul Harum, members of Black Sabbath and Bad Company, and possibly Townshend’s old bandmate Roger Daltrey.

What is it about the electric guitar that has gained it such iconic status? “It’s the only instrument of any kind — whether we are talking about an artist’s brush or a keyboard — that has had such an influence. It genuinely brought about a cultural revolution,” says Ian Spero, who conceived the Born To Rock exhibition that opens at Harrods next month, and which is currently running at the Museum of Decorative Arts and History in Dublin as Rock Chic: The Life and Times of the Electric Guitar. “It was the backdrop to the Vietnam War. It’s been the soundtrack of our lives. It’s the only instrument to affect the masses in this way.”

That sense of the instrument communicating the spirit of the masses is evident the moment you walk in to the exhibition. Pictures of Eric Clapton, Keith Richards, Lenny Kravitz, Jimi Hendrix and George Harrison greet the visitor at its entrance. The closest I’ve come to that sense was playing double bass on stage alongside the former Pogues multi-instrumentalist David Coulter and Steve “Boltz” Bolton, who had toured on lead guitar with a latter incarnation of The Who. The stage was smaller than either of them was used to, but when it was time for Boltz to unleash a power chord his face contorted, his hand ripped through the strings and his left leg soared high in the air; it was a true, visceral rock’n’roll moment felt by everyone in the hall.

For and of the masses: and intensely democratic. Because for every lovingly cared-for guitar on the walls, such as the black and mustard leopard paw-print custom five-string made for Keef to play on the Rolling Stones’s Voodoo Lounge tour, or the beautifully polished, carved steel of John Lee Hooker’s Johnson Dobro, there are others that speak of the rawness and aggression intimately connected with an instrument wielded not by some white-tie-and-tails conservatoire graduate, but by Everyman.

A Framus bass owned by the Animals stands propped up, its neck severed from the body and held together only by a few strings. The varnish has virtually been-stripped from the 1961 Fender Stratocaster owned by the Irish guitar hero Rory Gallagher, who recorded with the Stones, Muddy Waters and Jerry Lee Lewis, as well as selling millions of his own albums. The sweat that poured off him during performances, so the story goes, was so acidic that it destroyed the finish.

It only lends greater authenticity to an instrument that reeks of the primal masculinity of the working man, of the hunter-gatherer. It’s no coincidence that John Lennon, who was brought up in a relatively affluent area of Liverpool, should have proclaimed that “a working-class hero is something to be”. From the Charterhouse-educated founders of Genesis to the Clash’s late frontman Joe Strummer (whose father was a diplomat) and those two middle-class boys Pete Doherty and Donny Tourette, being associated with rock, a musical form whose foundation stone is the electric guitar, has been a means to leave behind bourgeois convention and a passport to demotic credibility.

As the cultural commentator Ted Polhemus writes of the electric guitar’s role in the 1990s: “Like its badly behaved parent, punk, grunge took things back to basics, once again — just as had happened in the 1960s with the birth of rock, and then in the 1970s with the birth of punk — establishing the axe as the definitive icon of rebellion against a complacent, tepid, insipid status quo. It did indeed smell like teen spirit. The kids were all right and they were armed with electric guitars.”

Along with rebellion, electric guitar-based music has always emphasised another aspect of man that the more polite conventions of earlier forms at least appeared to conceal — sex. Leave aside the obvious point about how the sturdy rod of the guitar’s neck thrusts out from above the player’s groin. Even the shyest of men can be transformed into a strutting peacock when displaying such a powerful tool. “It’s always the lead singer or the lead guitarist who gets the girls,” Spero adds. And how. If Bill Wyman could calculate that he’d slept with 278 girls between 1963 and 1965 — and he was only a bass player — what enticing opportunities must await the axe hero?

The point is that any man can dream of being such a figure. “The electric guitar is a relatively inexpensive instrument,” says Spero, “and you can get somewhere on it if you work hard enough, whatever kind of education you’ve had. It’s very aspirational.”

It can also be a means of expression for those who find it difficult to articulate feelings of whatever kind in other ways. Think of Noel Gallagher’s appearances on talk shows, and you recall a dash of laconic wit, the odd curdled ladling of sarcasm. Ballads such as Don’t Look Back In Anger suggest another side to the less pugilistic of the Gallagher brothers, one that finds an outlet when his guitar can do the speaking.

Think also of the armies of air guitarists, most joyously captured on film in Wayne’s World when the main characters headbang along to Brian May’s solo from Bohemian Rhapsody.There are air guitar world championships now, and in Australia government scientists have created a high-tech T-shirt that transforms, via a remote computer, the imaginary power chords of the air guitarist into actual sounds.

It took the electric guitar three decades to become an iconic instrument in the 1960s.The very first model, invented by George Beauchamp in 1931, was the Rickenbacker “Frying Pan”. On display in Dublin, it looks more like a bizarrely extended version of George Formby’s ukelele than its sturdier successors that would conquer the world. From such origins, however, mixed with the blues descended from Robert Johnson, the gradual blurring of the racial divide in 1950s America, and the advances made by Les Paul, Leo Fender and others, came the electric guitar and the rock music that could not exist without it.

Tony Blair may have been the first prime minister to pick away at his Stratocaster in Downing Street, dreaming, perhaps, of what might have been. He won’t be the last. The electric guitar has a power that no man can resist. After all, as Polhemus writes: “Even now it still looks, and in the right hands sounds, like something stolen from the gods — or, maybe more likely, a gift from the devil.”

Harrods Rocks runs from February 2 to March 3. For information, www.harrods.com