While the dust of the September 11 attacks still settled, the controversial media company Clear Channel sent out a list of more than 150 songs it deemed to be "lyrically questionable” to its network of 1,172 radio stations across the US.

Three days after the attack, the now-famous memo was emailed with 158 tunes - and all songs by Rage Against the Machine - which some of its program directors felt would be too sensitive to play in the aftermath of what is called the world’s deadliest “terrorist” attack.

Ever time someone mention's that Clear Channel "banned" song list from 9/11 I feel, as an employee at the time, like I have to defend it. — Kent Taylor (@mrradioguy) September 12, 2015

The existence of the list was no secret with reports in 2001 detailing how the corporation had banned the songs, although some stations chose to play some of the songs.

Many are related to flying, guns, fire, and death, but others symbolize how raw and exposed Americans felt in those dark days.

Movie and television producers also tweaked their output after the attack, including a one-off episode of the NBC series 'West Wing' which compared the Islamic extremism of al-Qaeda to the Christian fundamentalism of the KKK and acknowledged the perpetrators “specific complaints” like “troops in Saudi Arabia, sanctions against Iraq, and support for Egypt.”

Cautious Clear Channel radio stations were fearful of offending their audience of 110 million people, although 15 years later, the list has become a cultural timepiece.

Saw a list of songs that Clear Channel urged their stations NOT to play after 9/11. Of course, had to make an iTunes playlist immediately. — ShouldBeWriting (@MintRainbow1) September 12, 2015

The media company denied it was an outright ban, but instead “an effort to help people be sensitive to the unthinkable environment.”

“It's been somehow turned into some sort of evil attempt to control pop music, and that's absurd,"said Clear Channel spokeswoman Pam Taylor.

They were also keen to explain that the list wasn’t issued by the head office, but was instead ''a grassroots effort that was apparently circulated among program directors.''

Some songs include Billy Joel's 'Only the Good Die Young,' Bob Dylan's 'Knockin' on Heaven's Door,' Drowning Pool’s 'Bodies,' James Taylor's 'Fire and Rain,' and Black Sabbath’s 'Suicide Solution.'

The most astonishing thing abt this Clear Channel 9/11 playlist is that someone put it together. Like they brainstormed, & there were laughs — Cyber Mango (@cybermango) September 14, 2015

Others on the list highlight what the AV Club described as a “knee jerk reaction” to the tragic events, with Slate writing in September 2001 that many of the songs on the list were “ridiculous in their tenuous connection to anything even remotely offensive to survivors of the Sept. 11 attack.”

Here are some of songs featured on the list and the possible rationale Clear Channel executives may have been using.

The Bangles - Walk Like an Egyptian

The vague references to the Middle East and, as we discovered later, the national origin of 19 of the accused hijackers.

The Beatles - Ob La Di, Ob La Da

The lyric “Life Goes On” and general upbeatness.

Alien Ant Farm – Smooth Criminal

Your guess is as good as ours.

Rolling Stones - Ruby Tuesday

September 11, 2001 was on a Tuesday.

All songs by Rage Against the Machine

Just because.

Louis Armstrong – What a Wonderful World

The world wasn’t feeling very wonderful.

Creedence Clearwater Revival - Travelin' Band

It mentions the word “flying” at one point.

The Beatles – Ticket to Ride

Because people have to buy tickets to get on a plane?

Frank Sinatra – New York, New York

Don’t remind people where it happened.

John Lennon - Imagine

Didn’t want people imagining “there's no heaven,” with or without 72 virgins.

Tom Petty - Free Fallin'

OK, that one makes sense.

Here’s the full list of songs on the list:

3 Doors Down, “Duck and Run”

311, “Down”

AC/DC, “Dirty Deeds”

AC/DC, “Hell’s Bells”

AC/DC, “Highway to Hell”

AC/DC, “Safe in New York City”

AC/DC, “Shoot to Thrill”

AC/DC, “Shot Down in Flames”

AC/DC, “TNT”

Ad Libs, “The Boy from New York City”

Alanis Morissette, “Ironic”

Alice in Chains, “Down in a Hole”

Alice in Chains, “Rooster”

Alice in Chains, “Sea of Sorrow”

Alice in Chains, “Them Bone”

Alien Ant Farm, “Smooth Criminal”

All Rage Against The Machine songs

Animals, “We Gotta Get Out of This Place”

Arthur Brown, “Fire”

Bangles, “Walk Like an Egyptian”

Barenaked Ladies, “Falling for the First Time”

Barry McGuire, “Eve of Destruction”

Beastie Boys, “Sabotage”

Beastie Boys, “Sure Shot”

Billy Joel, “Only the Good Die Young”

Black Sabbath, “Sabbath Bloody Sabbath”

Black Sabbath, “Suicide Solution”

Black Sabbath, “War Pigs”

Blood Sweat and Tears, “And When I Die”

Blue Oyster Cult, “Burnin’ For You”

Bob Dylan/Guns N Roses, “Knockin’ on Heaven’s Door”

Bobby Darin, “Mack the Knife”

Boston, “Smokin”

Brooklyn Bridge, “Worst That Could Happen”

Bruce Springsteen, “Goin’ Down”

Bruce Springsteen, “I’m On Fire”

Buddy Holly and the Crickets, “That’ll Be the Day”

Bush, “Speed Kills”

Carole King, “I Feel the Earth Move”

Cat Stevens, “Morning Has Broken”

Cat Stevens, “Peace Train”

Chi-Lites, “Have You Seen Her”

Creedence Clearwater Revival, “Travelin’ Band”

Dave Clark Five, “Bits and Pieces”

Dave Matthews Band, “Crash Into Me”

Dio, “Holy Diver”

Don McLean, “American Pie”

Drifters, “On Broadway”

Drowning Pool, “Bodies”

Edwin Starr/Bruce Springstein, “War”

Elton John, “Benny & The Jets”

Elton John, “Daniel”

Elton John, “Rocket Man”

Elvis, “(You’re the) Devil in Disguise”

Everclear, “Santa Monica”

Filter, “Hey Man, Nice Shot”

Fontella Bass, “Rescue Me”

Foo Fighters, “Learn to Fly”

Frank Sinatra, “New York, New York”

Fuel, “Bad Day”

Godsmack, “Bad Religion”

Green Day, “Brain Stew”

Happenings, “See You in Septemeber”

Hollies, “He Ain’t Heavy, He’s My Brother”

J. Frank Wilson, “Last Kiss”

Jackson Brown, “Doctor My Eyes”

James Taylor, “Fire and Rain”

Jan and Dean, “Dead Man’s Curve”

Jerry Lee Lewis, “Great Balls of Fire”

Jimmy Hendrix, “Hey Joe”

John Lennon, “Imagine”

John Mellencamp, “Crumbling Down”

John Mellencamp, “I’m On Fire”

John Parr, “St. Elmo’s Fire”

Judas Priest, “Some Heads Are Gonna Roll”

Kansas, “Dust in the Wind”

Korn, “Falling Away From Me”

Led Zeppelin, “Stairway to Heaven”

Lenny Kravitz, “Fly Away”

Limp Bizkit, “Break Stuff”

Local H, “Bound for the Floor”

Los Bravos, “Black is Black”

Louis Armstrong, “What A Wonderful World”

Lynyrd Skynyrd, “Tuesday’s Gone”

Martha & the Vandellas, “Nowhere to Run”

Martha and the Vandellas/Van Halen, “Dancing in the Streets”

Megadeth, “Dread and the Fugitive”

Megadeth, “Sweating Bullets”

Metallica, “Enter Sandman”

Metallica, “Fade to Black”

Metallica, “Harvester or Sorrow”

Metallica, “Seek and Destroy”

Mitch Ryder and the Detroit Wheels, “Devil with the Blue Dress”

Mudvayne, “Death Blooms”

Neil Diamond, “America”

Nina, “99 Luft Balloons/99 Red Balloons”

Nine Inch Nails, “Head Like a Hole”

Norman Greenbaum, “Spirit in the Sky”

Oingo Boingo, “Dead Man’s Party”

P.O.D., “Boom”

Paper Lace, “The Night Chicago Died”

Pat Benatar, “Hit Me with Your Best Shot”

Pat Benatar, “Love is a Battlefield”

Paul McCartney and Wings, “Live and Let Die”

Peter and Gordon, “A World Without Love”

Peter and Gordon, “I Go To Pieces”

Peter Gabriel, “When You’re Falling”

Peter Paul and Mary, “Blowin’ in the Wind”

Peter Paul and Mary, “Leavin’ on a Jet Plane”

Petula Clark, “A Sign of the Times”

Phil Collins, “In the Air Tonight”

Pink Floyd, “Mother”

Pink Floyd, “Run Like Hell”

Pretenders, “My City Was Gone”

Queen, “Another One Bites the Dust”

Queen, “Killer Queen”

Red Hot Chili Peppers, “Aeroplane”

Red Hot Chili Peppers, “Under the Bridge”

REM, “It’s the End of the World as We Know It”

Rickey Nelson, “Travelin’ Man”

Rolling Stones, “Ruby Tuesday”

Saliva, “Click Click Boom”

San Cooke Herman Hermits,, “Wonder World”

Santana, “Evil Ways”

Savage Garden, “Crash and Burn”

Shelly Fabares, “Johnny Angel”

Simon And Garfunkel, “Bridge Over Troubled Water”

Skeeter Davis, “End of the World”

Slipknot, “Left Behind, Wait and Bleed”

Smashing Pumpkins, “Bullet With Butterfly Wings”

Soundgarden, “Blow Up the Outside World”

Soundgarden, “Fell on Black Days,” Black Hole Sun”

Steam, “Na Na Na Na Hey Hey”

Steve Miller, “Jet Airliner”

Stone Temple Pilots, “Big Bang Baby,” Dead and Bloated”

Sugar Ray, “Fly”

Surfaris, “Wipeout”

System of a Down, “Chop Suey!”

Talking Heads, “Burning Down the House”

Temple of the Dog, “Say Hello to Heaven”

The Beatles, “A Day in the Life”

The Beatles, “Lucy in the Sky with Diamonds”

The Beatles, “Obla Di, Obla Da”

The Beatles, “Ticket To Ride”

The Clash, “Rock the Casbah”

The Cult, “Fire Woman”

The Doors, “The End”

The Gap Band, “You Dropped a Bomb On Me”

Third Eye Blind, “Jumper”

Three Degrees, “When Will I See You Again”

Tom Petty, “Free Fallin’”

Tool, “Intolerance”

Tramps, “Disco Inferno”

U2, “Sunday Bloody Sunday”

Van Halen, “Jump”

Yager and Evans, “In the Year 2525”

Youngbloods, “Get Together”

Zombies, “She’s Not There”