Civil Defense in Minnesota, 1950–1974

During the extended Cold War standoff between the United States and the Soviet Union, many Minnesotans prepared for the terrifying possibility of nuclear war by participating in a variety of civil defense efforts. The civil defense strategies employed in Minnesota changed significantly as the perceived military threat evolved.

In the years immediately following World War II, the United States and the Soviet Union emerged as the two most powerful nations in the world—and as geopolitical rivals. The Soviets’ blockade of Berlin in 1948 and their successful test of an atomic bomb in 1949 confirmed that a global superpower competition was at hand. The outbreak of the Korean War in 1950 and subsequent suspicions of covert Soviet involvement in the conflict only deepened the U.S.–U.S.S.R. rivalry. As tensions between the two countries increased, the threat of atomic warfare loomed larger.

In December 1950, a new federal agency, the Federal Civil Defense Administration, began working with state governments to implement programs designed to help citizens survive a nuclear attack. A few months later, Minnesota established the Civil Defense Department to coordinate all civil defense efforts in the state.

“Duck and Cover” Period

During the first few years of Minnesota’s civil defense mobilization, state and local officials repeatedly assured the public that nuclear war was survivable. “With a dependable warning system and properly constructed shelters you are likely to survive an atom bomb blast,” the Minneapolis Star reported. School children were taught to “duck and cover” in the event of an atomic bomb flash. Homeowners were urged to prepare refuge rooms equipped with canned food, flashlights, and other emergency supplies. Civil defense officials believed that preparation was one of two primary keys to survival.

The other key was time. U.S. military planners assumed that if the Soviets attacked, they would use long-range bombers armed with atomic weapons. Radar could detect incoming enemy aircraft in some cases, but not all. Additional safeguards were needed.

In 1950, the U.S. Air Force reactivated the Ground Observer Corps (GOC), a World War II-era network of civilian volunteer plane spotters. GOC volunteers staffed observation posts and tracking offices known as “filter centers.” They constituted an extra early warning system that supposedly would give civilians the time they needed to seek shelter.

Minnesota boasted the largest GOC network in the United States. In 1954, near the program’s zenith, more than fourteen thousand volunteers staffed 460 active observation posts throughout the state. Those numbers were much smaller than what the Air Force deemed necessary, but they still represented an impressive commitment when compared to volunteer statistics in other states. Minnesota ground observers regularly reported plane sightings to the regional filter center in Minneapolis, but never spotted an enemy aircraft.

Evacuation Period

In 1952, the United States successfully tested the world’s first hydrogen bomb. It was estimated to be one thousand times more powerful than the atomic weapons previously developed by the United States and the U.S.S.R. The following year, the Soviets successfully tested their own H-bomb. The Cold War entered a new, more frightening phase. Civil defense officials in the United States stopped assuring Americans that they could survive a direct nuclear blast. Instead, they made plans to evacuate cities in the event of a Soviet attack.

The centerpiece of the new evacuation strategy was a nationwide series of practice drills called “Operation Alert.” Each year, beginning in 1954, cities throughout the country tested their civil defense readiness during a hypothetical nuclear attack. State and local civil defense officials were told to assume that citizens living in targeted cities would survive only if they evacuated to outlying areas.

In Minnesota, the annual Operation Alert drills mostly served to remind Twin Cities residents that getting out of town was the only way to survive an H-bomb blast. Newspapers published maps showing how an H-bomb explosion over a particular landmark (the Lake Street Bridge, for example) would devastate both Minneapolis and St. Paul.

Estimates from the first Operation Alert exercise showed that an H-bomb attack on the Twin Cities would kill more than sixty-seven thousand people in Minneapolis alone—even with a successful evacuation of downtown. The city’s civil defense director admitted the number would be much higher if the evacuation failed to go as planned.

Fallout Shelter Period

Federal, state, and local civil defense officials had always assumed that the public would have time to seek shelter or evacuate if radar and ground observers detected Soviet bombers on the way to U.S. targets. By the late 1950s, that assumption no longer made sense. In 1957, the Soviets conducted the world’s first successful test of an intercontinental ballistic missile (ICBM). That same year, they used a similar rocket to launch the satellite Sputnik I into earth orbit. The U.S.S.R. now possessed the technology to deliver a nuclear warhead to the United States in a matter of minutes.

Civil defense planners no longer had time on their side. Strategies shifted again. The Ground Observer Corps was deactivated in 1959. The last Operation Alert exercises were held in 1961. Plans for city evacuations were abandoned. In their place, civil defense officials began focusing on fallout shelters, where the survivors of a nuclear attack could theoretically protect themselves from radioactivity. The new strategy resulted in networks of public shelters marked by distinctive black-and-yellow civil defense signs. It also encouraged the building of smaller fallout shelters in private homes.

By 1966, Minnesota had nearly twenty-five hundred public fallout shelters stocked with food, water, medical supplies, and radiation detection equipment. Civil defense officials estimated that those shelters could accommodate more than 1.3 million people. The shelters were located in both public and private buildings. One civil defense official joked that Minneapolis’s best shelter was in the sub-basement of the Radisson Hotel, which was conveniently located next to the storage room of the Haskell’s liquor store. Another sixty thousand Minnesotans had access to home fallout shelters.

Phase Out

Minnesotans’ interest in civil defense spiked during high-stakes Cold War confrontations like the 1961 Berlin crisis and the 1962 Cuban missile crisis. It quickly diminished, however, once the perceived threat receded. Civil defense officials often lamented that public apathy was the biggest challenge they faced. As the years went on, new challenges arose from critics who argued civil defense was a “grand illusion” meant to lull people into the false belief that they could win and survive a nuclear war.

In the mid 1960s, the state Civil Defense Department started shifting its focus from nuclear war to natural disasters. In 1969, it became a division of the Minnesota Department of Public Safety. A few years later, it was renamed the Emergency Services Division. The state’s Cold War-era civil defense program unofficially ended during the 1970s, when many of the old public fallout shelters of the 1960s were emptied of their emergency supplies. By that time, the high-protein wheat crackers stocked in most shelters had gone stale or rancid. They were sold for cattle and hog feed.