Saturday night, armed with a new batch of songs from the album All That You Can’t Leave Behind that hark back to the band’s pre-Achtung Baby glory days and a new post-Sept. 11 sense of purpose, U2 proved why they are the world’s greatest rock band.

For two-plus hours, Bono stalked the stage and heart-shaped catwalk that extended into the audience like a man on a mission. Joined by ace guitarist, The Edge, the two stars worked the crowd like a pair of twenty-year-old kids playing in a smoke-filled bar with something to prove as they mugged for the cameras.

They shook hands with audience members, and gratefully accepted a flag that had Old Glory on one side and Ireland’s colors on the other.

Bono even kissed the hand of a female photographer while leaning in front of her as if to propose. With the house lights still up, U2 kicked things off with a pair of tunes from their latest album including the hit single “Beautiful Day.”

The energy level peeked early and never floundered. Highlights included an inspired offering of politically charged older songs such as “Sunday Bloody Sunday,” “New Year’s Day” and “Pride (In the Name of Love).”

Other fan pleasers included solid renditions of past chart-toppers such as “Where the Streets Have No Name” and “Still Haven’t Found What I’m Looking For.”

Covers included Marvin Gaye’s 1960s protest anthem, “What’s Going On,” as well as excerpts from “Here Comes the Sun” and “My Sweet Lord,” in memory of recently deceased Beatle George Harrison.

During the encore, an audience member handed Bono a white T-shirt that read: I (heart) N.Y. For the show’s finale, Bono wore the shirt over his own as he strummed his acoustic guitar and sang the words to “One,” a touching meditation on the power of love. Meanwhile, the names of the Sept. 11 victims were displayed on a large screen behind the stage.

It was a heartfelt gesture that capped off an emotionally charged evening that proved rock ‘n’ roll can offer a sound salvation in times of despair.

Tech-rockers Garbage opened the show with a sultry performance by front-woman Shirley Manson.

Along with cuts from their new album, beautifulgarbage, the band also appeased audience members with wattage-intensive takes on the hits “Stupid Girl” and “I’m Only Happy When it Rains.”