Dr. John has always been a superior songwriter. A master conceptualist, he envisions lyrics and music as part of an overall vision. He is one of the very few denizens of the fertile New Orleans R&B scene of the 1950s to translate the miniaturist art of the three-minute hit into the longplayer ethos of funk and rock. His conceptual power travels further into his interpretations of other writers’ songs. Unlike most New Orleans groups who use cover material as simple fodder for jamming grooves with little regard for the original song structure, Mac Rebennack translates everything he touches into Dr. John material.

Aside from his apocalyptic glimpse at the chaos of late-1960s American culture on his second album, Babylon, Rebennack has rarely ventured into topical material. In fact, many of his lyrics make up a kind of secret language corresponding to the sound of his music. But he has been politicized by what he views as a wholesale governmental betrayal of New Orleans before and after Katrina, beginning with the shoddy construction of the levees that failed in the storm surge and continuing through the corruption and deceit of the recovery effort. He’s written about this for the Voices of the Wetlands, but now he’s devoted nearly an entire album to the subject, City That Care Forgot.

This subject matter is so important to Dr. John that he has enlisted several writers to help him put his point across, including a trusted old friend, Bobby Charles, the author of “Walking to New Orleans.” The trademark Dr. John delivery, relaxed and offhanded, still comes across in large part, but it’s spiked with the unmistakable catch-in-the-throat sound of an angry man. It’s a startling transition for those who’ve followed him over the years, and it gets your attention.

There are several cameo pieces here—the inspirational “You Might Be Surprised,” the environmental anthem “Save Our Wetlands,” and a great song about the city’s controversial campaign to stamp out second line celebrations, “My People Need a Second Line” with a terrific guest shot from Trombone Shorty.

Over the course of the rest of the record, Rebennack outlines the framework of an epic American tragedy in point-by-point observations, drawing on what some might call urban myths to paint a powerful picture of systemic betrayal and genocide.

In “Keep on Going,” he references the Hansel and Gretel story of being lost in a forest to describe those driven from their homes by the storm. They left that trail of bread crumbs, but it was washed away, and now “the only home you got is your own self.” He mythologizes himself as “a samurai of the Holy Lost Cause,” and asserts that the levees were blown “with intention.” He attributes motivation to that intention in “Land Grab,” accusing the politicians and their corporate backers of trying to run the people of the Lower Ninth Ward and St. Bernard off their homes in “the biggest land grab since Columbus.”

Everywhere he turns, he sees evil in the world—trigger-happy Blackwater private security forces who used deadly force without legal restraint in the chaotic days after the storm, much needed resources wasted in Iraq, and behind it all Bush, Cheney and Halliburton. But alongside the anger is a deep wellspring of sorrow. In “We’re Getting’ There,” he writes of people he knows losing the battle to rebuild their homes and giving up. “Ask anybody if they knew a friend that died from suicide,” he notes coldly.

That sorrow reaches its apotheosis as a motivating factor in Rebennack’s world on “Stripped Away,” a loving remembrance of New Orleans before the storm.

Few people have done a better job of codifying the spirit of New Orleans over the years, offering tributes to its musical forefathers and participating directly in nearly a half century of its most important music. On City That Care Forgot he may have fashioned its most elegant obituary.