​Almanac: A mock nuclear attack

And now a page from our "Sunday Morning" Almanac: June 14th, 1954, 61 years ago today ... the day Americans took time out to hunker down.

The nationwide drill, "Operation Alert," was driven by fears of a Soviet nuclear attack ... fears so powerful that even jaded New Yorkers were willing to comply. Less than two minutes after the "take cover" signal was given, the streets were cleared. Times Square was deserted.

Not that New York was the only target of the presumed Soviet attack. Far from it: 20 U.S. cities in all conducted some sort of public exercise, including Washington, D.C., where President Eisenhower was seen doing his part: A helicopter landed on the White House lawn, to ferry the president to a secret mountaintop relocation center.

The urgency of that day reflected the overall nuclear anxiety of the times -- an anxiety that made its way into the nation's schoolrooms. The civil defense film, "Duck and Cover" (1951), taught a whole generation of schoolchildren to be prepared for an atomic attack that could come at any time:

"When there's a flash, duck and cover!"

How effective all that ducking and covering would have been was in doubt even then.

And even though the nationwide drill on that long-ago June morning was judged a success, Civil Defense officials calculated that at least two million New Yorkers would have died in a real attack.

Nationwide, the toll would have exceeded 12 million.

Fortunately, those estimates have never been put to the test.