When Green Day toured behind its ambitious American Idiot record a half-decade ago, it was about a return to mega-stardom. This time, it's about legacy.

The pop-punk progenitors seem bent on cementing their place among the current rock elite, with an eye on the all-time best live acts. Tuesday's all-in performance at the Forum in Los Angeles was a mandate for the crowd to remember this show, the last of a seven-week North American jaunt. And memorable it was.

The focus was not on the music, though the band is promoting its second consecutive concept album, 21st Century Breakdown. No, the emphasis of this nearly three-hour marathon was squarely on entertainment and creating that sense of community that so few important rock acts seem to care about anymore. Sure, it was Professional Show Business, calculated every step of the way. But it also was one of the most flat-out enjoyable arena shows this town has seen in years.

Has Billie Joe Armstrong been keeping a journal of his band's gigs since their spectacular breakout in 1994 -- filing away every trick that ever got a rise from any crowd to unleash them all on this tour? It seemed that way. The fiesty frontman pulled no punches in his zeal to obliterate the wall between performer and patron, simply insisting that the crowd enjoy themselves.

It was a syllabus for Arena Rock 101: booming pyrotechnics, call and response, count-offs, incited clap-alongs and arm waves, name-checking the tour stop (Thank God for Los Angeleees!), venturing into the crowd, bringing folks onstage (he yanked out one youngster's earplugs and hurled them away in mock disgust), cannon-firing T-shirts and TP into the throng, making exaggerated and drawn-out band intros. There even was a full mooning.

And the crowd lapped it up, acquiescing to Armstrong's every demand. He told stories and often made a point of inciting communal pride. This is a f***ing rock 'n' roll show, not a tea party, he admonished. You listen to Coldplay on your own f***ing time! His easy command of the stage and crowd recalled vintage Springsteen.

Among songs that spanned its multiplatinum career, the band deployed teaser snippets of rock classics by bands renowned for their concert prowess, as if lobbying for inclusion into an exclusive club -- from Satisfaction and Stairway to Heaven to Ain't Talkin' 'Bout Love and Sweet Child o' Mine. A raucous version of Green Day's own King for a Day devolved into a show-stopping celebration of Shout, complete with a sax-and-kazoo breakdown and side trips to Tom Petty, the Doors and Beastie Boys.

Everything was meticulously planned for maximum effect; Armstrong even coached folks he brought onstage to dive off it at a certain time. That might be anti-punk, but so what? It was pure rock 'n' roll, the creaky Forum adding to the old-school ambience of a great concert by one of today's greatest live bands -- one that's still firmly in its prime.

Fall Out Boy opened, likely for an opportunity to take notes.