“All or Nothing” (Atlantic), the new album by Fat Joe, is aptly named. After 13 years in the rap game, opportunity is knocking for the Bronx-born rapper. It won’t knock twice.

Several factors conspire to make this Fat Joe’s make-or-break moment. First, he’s riding high on the popularity of last summer’s hit song “Lean Back,” which earned his group Terror Squad a grammy nomination and a no. 1 Billboard single. It was a breakthrough for Fat Joe and explains the enormous push his new album is getting.

A second factor is the rising tide of the Puerto Rican hip-hop/dance-hall fusion known as reggaeton. Half Puerto Rican himself, Fat Joe is enormously popular among Puerto Rican fans and artists. (His appearance on the Hot 97 float at Sunday’s Puerto Rican Day Parade drew deafening cheers.) And he’s setting himself up as a sort of father figure to the movement. He appeared on Ivy Queen’s last album and performed alongside Tego Calderon (who, as of last week, is also signed to Atlantic) at the big Madison Square Garden Megaton concert in March. He’s also organizing the first-ever summer tour focused on Latin Urban music, called the Libertad Music Festival 2005. Although “All Or Nothing” sticks strictly to hip-hop, reggaeton’s momentum can only help his own.

The third and perhaps deciding factor is the beef Fat Joe’s embroiled in at the moment with 50 Cent.This is the hip-hop equivalent of a heavyweight title shot – a once-in-a-lifetime chance for the underdog to make a name for himself. Joe realizes the opportunity: “Ain’t been this much hype since that Nas and the Hov shit,” he raps, referring to the legendary Nas/Jay-Z beef. While Joe’s unlikely to unseat 50, a good showing could do a lot for him.

A closer look at the spat provides a good diagnosis of Fat Joe’s predicament. It began last year when Joe appeared on Ja Rule’s diss track “New York.” Having dispatched Ja, 50 took aim at Joe on the song “Piggy Bank” from his album “The Massacre.” “That fat nigga thought ‘Lean Back’ was ‘In Da Club’/ My s– sold 11 mil, his shit was a dud,” raps 50.

It’s something of a bait and switch. Beefs usually revolve around street credibility. 50 concedes that Joe has street support, so he instead makes it a contest of album sales – essentially a measure of his popularity with the white suburbs. “Yeah, hommies in New York like your vocals/but that’s only in New York, nigga, your ass is local,” he says of Joe. And he’s got a point: Despite having one of the hottest singles of 2004 with “Lean Back,” Terror Squad’s album only sold some 400,000 copies.

The challenge for “All or Nothing” is to break Fat Joe onto the national stage and break into the suburban shopping malls. The album is good enough to do it several times over. Joe assembles an all-star cast of collaborators and producers who helped him cram it with radio-ready hits. “Safe 2 Say” has a clapping, Wurlitzer-driven beat by Just Blaze that recalls his work on Jay-Z’s “Black Album.” “Get It Poppin’,” featuring Nelly, is a light, frothy party jam compliments of Scott Storch, the man who supplied Fat Joe with the beat for “Lean Back.” That song also makes a curtain call on the album, lightly synthed out by Lil Jon. The more noticeable change, however, is the addition of Mase and Eminem, who deliver sharp verses and, more importantly, considerable star power. (It’s a testament to how fluid allegiances are in the rap world that 50’s mentor, Eminem, appears on the track. The most likely explanation is that it was recorded before the beef with 50 developed.)

The reappearance of “Hold U Down,” a J. Lo song featuring Fat Joe first released on her album “Rebirth” earlier this year, might give the impression that Joe is straining to fill out the album. But the opposite is true: Many of the best songs are the deep album cuts produced by longtime Fat Joe collaborators Cool & Dre (not to be confused with Dr. Dre). The duo has established itself among the beat-making elite in the last year, and they live up to their reputation here. The song “So Much More” sounds like a horror-soundtrack version of West Coast gangsta rap. “I Can Do U” features playfully seductive rhymes against a Prince-like synth-funk background. “Rock Ya Body” is full of crunked sci-fi sound effects and includes the most succinct articulation of the album’s street-meets-club vibe: “Who the f– you know like Cook (a Joe alias)/kill a nigga on a verse/make him dance on a hook,” raps Joe.

And his beef with 50? Joe fares pretty well. On “My Fofo,” his criticism boils down to the fact that 50 Cent sings more than he raps, and that he won’t leave his Connecticut compound without police protection. “Oh, yeah, you got 65 niggas on your team/and they’re not from South Side Jamaica Queens,” charges Joe, “they’re the boys in blue/I’m just speaking the truth/now we all see the bitch in you.”

But 50’s precautions are understandable. Joe opens the song saying “50, you gonna end up dead when you f–ing with Crack (another of Fat Joe’s aliases),” and ends with the ominous statement, “it’s gonna be a real ugly summer man.” Such threats are a part of the hip-hop pissing contest, and are usually nothing more than braggadocio. Let’s hope that’s the case here, as Joe’s set himself up for a career-changing summer.