Backstage at the Nassau Coliseum in suburban Long Island, the scene is no more chaotic than at any big hip-hop show. Headliner Busta Rhymes strides down a corridor, trailed by his entourage, the Flipmode Squad (named for Rhymes's own record label). There seem to be dozens of them, all male, all faintly watchful.

As they come through, oddly antiquated cellphones trilling, they exchange formal nods with the support act, Ludacris, and his entourage. With everyone decked out in capacious sportswear and complicated trainers, it's hard to tell who belongs to which group, but the cops clocking up overtime in the corner seem to have it worked out. They inspect the milling crews with practised eyes, and are studiously ignored in return.

It doesn't seem politic to ask the police whether they habitually patrol rap gigs wearing black SWAT-style jumpsuits and armed with machine guns. Actual machine guns, mind, rather than the fantasy ones that figure in the tall tales of gangsta rap, or the burst of sampled gunfire that opens Busta's current album, It Ain't Safe No More. But it's probably safe to assume that two mysterious recent shootings at the offices of Rhymes's management company play a part in the heavy security measures.

A sidewhiskered officer called Glen is surprisingly forthcoming. "Rival entourages all want to shoot each other," he says, doing a neat twirl with his gun so that it points at the floor rather than at your reporter. "Gangs are involved; we've heard the Bloods and the Crips notorious rival west coast gangs are around. So if people come in here with guns, we want to have bigger guns."

It is unlikely that so much as a paper clip could have been smuggled past the metal detectors at the backstage door, and anyway, Rhymes and Ludacris are mates. But it illustrates the jangled nerves affecting the platinum-selling MC, his sprawling entourage and those around them.

This has to be alarmism of the sort that besmirches hip-hop's image on both sides of the Atlantic, right? Well, maybe not entirely. When Busta, a dreadlocked Brooklyn giant, says it isn't safe, he's not speaking rhetorically. In January, assailants sprayed the Manhattan office of Violator Management - the team behind Busta, rap queen Missy Elliott and fashionable new MC 50 Cent - with bullets, shattering doors and windows.

No one was hurt either then or a month later, when Rhymes's unoccupied car was shot six times outside the company. But staff at Violator, one of hip-hop's most powerful management firms, were shaken by the apparently motiveless attacks. With the still-unsolved murder of his old friend Jam Master Jay of Run DMC fresh in everyone's mind, Busta stepped up security, and wore a bulletproof vest to the Grammy awards. Known over the course of six albums as hip-hop's comic motormouth, he isn't feeling funny these days.

Nonetheless, the Coliseum show passes without incident. Busta gambols about the stage, to all appearances the herbally refreshed life of the party. The crowd dance themselves into a stupor - Busta's party tunes are as popular in the white suburbs as in urban centres - and the backstage lot manage to refrain from killing each other.

Rhymes, born Trevor Smith, has been in the business for 12 years and is generally liked - which means he is an unlikely target for a rap feud, or "beef". Beefs can be complex and go back years, with both sides nursing grudges long after the original dispute has been forgotten. Busta has had his share of playground spats and name-calling, without which a rapper is considered a girl, but generally he's a lover rather than a fighter. His new single, I Know What You Want, is a balladic duet with Her Squeakiness Mariah Carey, and downright slushy. A-listed at Radio 1, it looks to be his biggest British hit.

His songs tend to be raucous party jams, such as the anthemic Woo-Hah! Got You All in Check, or wordy political commentary. Even tracks that disparage other MCs retain a sense of humour. A current example is the underground "dis track" Hail Mary, recorded in response to a verbal attack by Ja Rule (of the rival Murder Inc stable) that's doing the rounds on New York's mix-tape circuit. Busta raps: "If I recall, Violator used to manage you, nigga/ They took a closer look and realised you was an impostor/ There's never been a violator in the Murder Inc roster/ Dumb ass!"

This is the hip-hop equivalent of shouting: "Nyah-nyah, your mother's fat!"

Rhymes, a member of a breakaway Nation of Islam faction known as Five Percent Nation, is a combination of irrepressible clown and gibberish-speaking mystic. What he's not is a trouble-maker. Though he is serving five years' probation for a 1999 gun offence, the incident seems to have been an anomaly in an otherwise peaceful life centred around his family and Flipmode chums. So what's going on?

Violator's president, James Cruz, is willing to talk about rivalries in general terms. His office on the eleventh floor of a nondescript building in Manhattan's Garment District is stylishly minimal, down to the metal front door and walls.

"Oh, the walls and door didn't used to be metal," says the receptionist who buzzes us in. "They got all shot up. I'd just left work that day, and I got in the elevator just as they the gunmen got out of the other. They shot my desk, the wall - there was broken glass, the wall was broken."

Cruz, a goateed Puerto Rican from Brooklyn, shrugs. "It was a message," is his interpretation of the shooting. "But we don't know what message. They came up in the elevator, fired bullets and left." He cut his teeth working for the notorious Los Angeles label Death Row, and has been here before "I lived through this kind of stuff when I was there."

His experience of perpetual east coast v west coast beefs, which culminated in the murders of Tupac Shakur and Notorious BIG seven years ago, has taught him never to admit he is intimidated. "From the early days, rap's been built on battle. It's a social issue, from the hood and from the projects. If you get tested and you fail that test, they'll never leave you alone. But Busta doesn't throw the first punch.

"Can you bring in the dis tracks?" he calls to someone in the outer office. "The Jay murder has made people more concerned about rivalries. You shouldn't put your life on the line unless your family is threatened, but a lot of these guys take their crews entourages as their family."

An assistant enters with a pile of CDs, which Cruz pushes across the table. The Busta dis track, Hail Mary, is here, along with other insulting tit-for-tat numbers by Violator artists. So this is how Citizen Busta, 31 and a father of four, spends spare studio time, calling Ja Rule a "little faggot". Very handbags-at-dawn. Cruz shrugs again "When you're rich and successful, it's an ego thing."

Busta is headlining a show in Providence, Rhode Island, the day after the Nassau Coliseum gig, and he and Cruz will travel up separately from the Flipmode Squad. "We're going to get there right before the show and come right back to New York afterwards," says Cruz,tapping the tabletop, keen to conclude the conversation. He is clearly relieved that Busta will only be away from his New York home for two nights.

The Flipmode Squad's main female artist, Rah Digga, a winsome social-issues campaigner in the mould of Ms Dynamite, levels the blame for current problems not at MCs but their ubiquitous crews. "It's the entourage, or a knuckleheaded member of the entourage, who riles things up. If you're in a powerful situation, you travel in large groups as security, and the next thing you know, one guy starts arguing with another. They're often still on the streets and don't think that they might be dealing a bad blow to an artist's career."

Rah has her own entourage of seven, "but six are girls", she laughs. We're in the office of Flipmode, half a dozen blocks from Violator. When the Guardian and Busta's press officer arrive, we are scrutinised before we're admitted, the publicist's London accent apparently doing the trick.

Rah contends that MTV and the rap media - a substantial entity in America - "glorify" disputes between crews. "Right when guys might be about to squash a beef, a magazine does a story about it and blows it all up again. Generation X is being entertained by beefs between big stars. There's a beef between 50 Cent and Murder Inc that's been blown up out of all proportion, but rappers themselves mostly know that they're blessed to have all the stuff they have."

Rhymes himself submits to a few questions in his dressing room at Providence's main arena, the Dunkin' Donuts Center. Nobody finds the name amusing, least of all our man, who is having his ornate beard trimmed when we're ushered in. He and Cruz have just arrived, and, like everyone else, had to submit to a body search before they were allowed past arena security.

When Cruz opens his briefcase to be searched, he reveals a three-inch wad of notes. (When 50 Cent, who is also playing, turns up, his car is driven right into the backstage area, and he sits in the back seat until the last possible minute. While they are on stage, his backing rappers, who number about 10, perform in bulletproof vests, though 50 Cent risks baring his impressively hewn chest.)

Rhymes dresses like the Central Casting version of a successful rapper: two diamond studs in his left ear, hefty diamond watch and a blingy white leather jacket with "Flipmode" in six-inch letters on the back. Look for something equally zippy in his new "urbanwear" line, Bushi, which he hopes will rival the success of P Diddy's garish Sean John range. Rhymes is his range's best advert, though he has the advantage of being about 6ft 2in.

So, about these shootings... His look is flinty. "Shit happens, man. Fortunately, the worst case scenario was that the truck his Mercedes SUV needed work done anyway, so the insurance company cut me a cheque that allowed me to do more stuff than I'd planned, and it's got a new sound system now. Don't like what you do to my beard, man," he tells the hairdresser, who slows his clipping to a snail's pace.

What inspired the title It Ain't Safe No More? "It's not just about me - it's general, everything from war to the environment to rap beefs. And in terms of the way police target hip-hop and blame hip-hop for this and that," he adds tangentially. "Do you feel safe with the Middle East and George Bush and airplanes crashing into buildings?"

He eyes critically the curlicues the hairdresser has snipped into his foliage. "The government is weird to me. They conspire a lot, at the end of the day. They concoct things, they create environments that encourage people to function a certain way."

He looks grumpy, but suddenly relents and pecks me on the cheek as a Flipmoder appears to show us out.

In the backstage corridors it's the same scene as the previous night - milling entourages, armed police, watchful glances. All activity stops for an instant as support act Lil' Kim struts past in an appropriately tiny military uniform.

At the end of his set, Busta wastes no time in leaving, climbing into a people carrier with Cruz. A young armed officer steals a sympathetic glance at the Flipmode Squad. "They think they're going to shoot each other up," he says. And he shakes his head at the folly.