Those who refuse to learn from rock history are doomed to watch its repetition in kicky fad form, its intentions misunderstood and its inheritors mutated beyond recognition. So little wonder that D.C.’s hardcore muse and former minuteman Ian MacKaye bears the punk-rock torch with sometimes missionary zeal. The Argument, Fugazi’s eighth album, is a bracing corrective to the misconceptions of punk’s original intent. Point one: Punk “anarchy,” since dismissed as chaotic nihilism, is a reasonable and relevant response to greed-driven municipal destruction (“Cashout,” “Strangelight”) and malign neglect of citizenry (“Argument,” “Oh”). Point two: the do-it-yourself ethos that fetishizes instrumental cacophony and vocal intensity is not a function of anger or a form of anti-music but an aural manifestation of direct, humanistic expression (“Full Disclosure,” “Epic Problem”). Point three: Melodicism isn’t counter-revolutionary, pop triviality is (“Life and Limb”). And in every skewed guitar note and crackling drum beat, every cello stroke and modulation of MacKaye’s malleable voice, there’s a passion for rigor — intellectual, political and musical. That’s point four: Control isn’t weakness if it’s in service of the message. Melancholy and scabrous, this is an argument made through music, subtly rewriting punk’s rewritten history.