The National's Barclays Center triumph

The National never do things quickly.

The Brooklyn-by-way-of-Cincinnati alternative band had been around for more than a decade before its mainstream breakthrough with 2010’s “High Violet” album, which its most recent “Trouble Will Find Me” album followed into the Top 3 last month.

Its two-hour show last night at Barclays Center was a slow build, too, waiting until nearly the end to give its fans the emotional catharsis it wanted.

The band – singer Matt Berninger, guitarist brothers Aaron and Bryce Dessner, and rhythm section brothers bassist Scott and drummer Bryan Devendorf – opened with its two most traditionally arena-rocking songs, the new “Don’t Swallow the Cap” and its hit “Bloodbuzz Ohio,” from “High Violet,” to rev up the crowd and show that The National’s intimate, subtle music could fit in such a massive setting. Then, they collectively stepped off the gas.

It took a while for the crowd to settle down, clapping in unison though unprompted, screaming obscene devotions of love to Berninger (and that was just the guys). But soon the band’s lush, layered arrangements, augmented, at times, by a horn section and a string section, took hold and Berninger was able to tell his clever, moody stories in his deep, measured baritone.

They were actually able to convey the gorgeous longing of “England” well in this setting, with its unconventional lighting and video setup. No pure spotlights for The National members, no close-ups on the video screen behind them. When Berninger moved off the stage, he was barely lit.

It was all about setting the mood and preparing the slow build. By the time they reached their longtime encore “Mr. November” and Berninger began leading a scream-along of “I’m the new blue blood, I’m the great white hope” by walking into the huge crowd standing on the floor. That “Mr. November” feeling of trying to rage against doubt and talk yourself into success is a very National concern.

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For its final encore, The National led the crowd in a acoustic sing-along of “Vanderlyle Crybaby Geeks,” with its payoff line, “I’ll explain everything to the geeks” drawing extra emphasis and loud cheers each time it went around.

It took a long time, but The National has arrived. Never mind all the pop groups chasing the little girls, the geeks understand.

SETLIST: Don't Swallow the Cap / Bloodbuzz Ohio / Mistaken for Strangers / Sea of Love / Sorrow / Demons / Heavenfaced / Afraid of Everyone / Conversation 16 / Squalor Victoria / I Need My Girl / This Is the Last Time / Abel / Apartment Story / Pink Rabbits / England / Graceless / About Today / Fake Empire // ENCORE: I Should Live In Salt / Humiliation / Mr. November / Terrible Love / Vanderlyle Crybaby Geeks