On April 14, 1988, Public Enemy unleashed their second album, a dense, dizzying masterpiece of social outrage entitled 'It Takes a Nation of Millions to Hold Us Back.'

The group's debut album, 'Yo! Bum Rush the Show,' released the year before, received critical acclaim for its abrasive, sample-heavy sound. But frontman Chuck D was already planning something bigger for their follow-up: nothing less than the rap equivalent of Marvin Gaye's state-of-the-world masterpiece 'What's Going On.'

Of course, 'Nation' would sound nothing like that lush, warm album. Inspired rather than cowed by those who criticized their work as noise rather than actual music, Public Enemy decided to make everything this time out louder, faster, more complex and most importantly, noisier.

The album's second single, appropriately titled 'Bring the Noise,' sums up the group's approach perfectly. Chuck D's booming voice cuts through a thick, swirling blend of squealing guitars, samples, beats and scratches: "Soul on a roll but you treat it like soap on a rope / Cause the beats in the lines are so dope / Listen for lessons I'm saying inside music that the critics are all blasting me for."

Throughout the album, Chuck D and his comic foil Flavor Flav tackle a variety of social and cultural issues with directness and fury. Their views on the art of sampling and the corrupting influence of mass media are laid out in 'Caught, Can I Get a Witness?' and 'She Watch Channel Zero?!,' respectively.

The government's involvement in the deaths of African-American heroes is even called into question during 'Louder Than a Bomb' -- "You CIA, you see I ain't kiddin' / Both King and X they got rid of both / A story untold, true but unknown."

Other highlights include 'Black Steel in the Hour of Chaos,' a haunting prison break story narrated by Chuck D over a haunting piano sample, and the anti-drug screed 'Night of the Living Baseheads.'

The album quickly made Public Enemy one of the most important groups in hip-hop, with the staccato "tea kettle" samples from 'Rebel Without a Pause' and 'Don't Believe the Hype' dominating airwaves and boomboxes (remember, it was 1988) for months and the group's socially conscious lyrics inspiring a wave of like-minded peers.

The full story of the creation, message and impact of 'It Takes a Nation of Millions to Hold Us Back' is told in great, concise detail by Christopher R. Weingarten in an excellent book from the 33 1/3 series.

'Nation of Millions' would be the first of three straight genre-defining albums from Public Enemy, followed by 1990's expansive, less dense 'Fear of a Black Planet' and 1991's blunt, tightly wound 'Apocalypse 91... The Enemy Strikes Black.' As original DJ Terminator X and the Bomb Squad production team moved away from the group in the late '90s, the consistency and popularity of their albums began to wane -- although there were and continue to be numerous high points.

Most importantly, Chuck D's voice remains a national treasure and his messages continue to inspire. Public Enemy has reinvented itself by incorporating live instruments into their concerts and studio sessions, and maintains an active touring and recording pace. Last year, they releaseed two different studio albums, and the group will be inducted into the Rock and Roll Hall of Fame in April of 2013.

Watch Public Enemy Perform 'Bring the Noise'

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