Nuclear Apocalypse at 12th & Arch

Civil Defense Sign - Roosevelt Boulevard, August 29, 1951. (PhillyHistory,org)
Civil Defense Sign – Roosevelt Boulevard, August 29, 1951. (PhillyHistory,org)

As the 10th anniversary of the Hiroshima and Nagasaki bombings approached in 1955, horrors of nuclear war seemed closer, not farther away. Millions of American viewers were rattled to see the disfigured “Hiroshima Maidens” on reality TV (This Is Your Life), victims visiting the United States for reconstructive surgery. Even more frightening—if such a thing was possible—the arms race with the Soviet Union turned out ever larger and more destructive weapons.

The Soviets tested their first atomic bomb in August 1949. Four years later, they claimed to have the hydrogen bomb. In November 1955, they detonated it. Americans also had also been developing larger and more powerful warheads. In 1952, the U.S. detonated “Mike,” a 10.4 megaton hydrogen bomb with twice the explosive power of World War II. Two years after that, the Americans tested “Bravo,” a 15-megaton hydrogen bomb resulting in an explosion more powerful than anticipated. Bravo contaminated 7,000 square miles of the Pacific and blanketed the globe with fallout.

The possibilities of deploying nuclear weapons were very real. In 1950, President Truman admitted A-bombs were being considered in the Korean War. Five years later, President Eisenhower wouldn’t rule them out in the Formosa Straits Crisis. Americans grew increasingly distraught about the possibility, the probability, it seemed, that the United States would attack—or come under attack. And if this were to happen, when this happened, society as known would be over, replaced by a decimated, fragmented version managed by a government hidden deep underground.

The transition to this new, post-apocalyptic world would begin a few minutes before the bombs hit America’s soon-to-be-obsolete cities. If all went well, apocalypse management would begin with the wail of air-raid sirens signaling a mass exodus from the targets. And Civil Defense authorities figured that any city with a population of over 50,000 would be a target.

Reading Terminal: The Would-Be Soviet Target (
Reading Terminal: A Cold War target (

Operation Alert took place on June 15, 1955, a day that otherwise seemed like any other Wednesday. “Imaginary atom bombs ‘blasted’ Washington and 60 other American cities to theoretical rubble,” reported the Inquirer. “Thousands of officials, led by President Eisenhower, fled the capital and set up a scattered, skeleton government at sites up to 300 miles away.”  A Secret Service motorcade escorted the president and his entourage from the White House to “an undisclosed hideaway in a ‘mountainous, wooded area.’”

“Philadelphia was brought face-to-face with the grim realities of atomic war. A ‘surprise bomb’ hit the city at 2:11PM, “striking at 12th and Arch Sts. and theoretically making a wasteland of many square miles…” Operation Alert “brought traffic to a standstill throughout the Philadelphia area. … Sidewalks were emptied of pedestrians and the city’s full complement of Civil Defense personnel and equipment went into action.”

“Mayor Joseph S. Clark and members of his Cabinet left City Hall…to take command at the secret central control station set up in the Northeast. … Philadelphia ‘evacuees’ were moved out of the city…to previously prepared reception centers in Bucks, Delaware and Montgomery counties.” Police led convoys from Bridesburg to Council Rock High School in Newtown and from Germantown to Abington High School. More than 1,600 evacuated West Philadelphia in 300 cars and buses.

12th and Arch Street from Reading Railroad Bridge, February 5, 1959. (PhillyHistory,org)
Evidence of life at 12th and Arch Streets in 1959, four years after Operation Alert. (PhillyHistory,org)

Casualties would be devastating. Officials “counted” 760,340 “dead” in Philadelphia and 363,860 “injured” reported The New York Times. More than three quarter of a million would be “homeless.” Across the nation, according to the Civil Defense Administration, “a partial presumed toll of more than 5,000,000” had died; nearly as many were injured. Other officials projected even more: 8.5 million Americans dead, 8 million injured and 10 million displaced. Best guesses had 25 million without food or water.

“Staggering,” said Eisenhower, who had previously admitted “if war comes, it will be horrible. Atomic war will destroy our civilization. It will destroy our cities. …[it] would not save democracy. Civilization would be ruined… No one was going to be the winner. … The destruction might be such that we…go back to bows and arrows.”

Even so, the Eisenhower Administration supported the policy known as MAD—mutually assured destruction—and the idea that Americans were “Better dead than red.”

Not everyone bought into Operation Alert, and not everything worked as planned on June 15, 1955. Schoolchildren spotted Eisenhower’s “secret” caravan and shouted, “Hey Ike!” as it sped by. In New York, resisters occupied park benches across from City Hall. One official in the District of Columbia declared: “the test will teach us nothing.” Another in Peoria, Illinois refused to cooperate, adding “I can’t see a lot of people running around with armbands on.” And in Flint, Michigan the siren system was broken. Everyone in Flint “died” without ever hearing the Cold War’s piercing, futile wail.

[Sources: “President Leads Flight of Officials To Hideaway Capital in Atom Test,” and “202,000 ‘Casualties’ Listed In City in Mock A-Bombing” in The Philadelphia Inquirer, June 16, 1955; Anthony Leviero, “’H-Bombs’ Test U.S. Civil Defense: 61 Cities ‘Ruined,’” New York Times, June 16, 1955; and Dee Garrison, Bracing for Armageddon: Why Civil Defense Never Worked ((Oxford University Press, 2006).]