CBS News Correspondent Sharyl Attkisson reports that the declassified data may have also helped Pakistan and India, which conducted dueling nuclear tests just days apart last year, upping the ante in a new arms race among old enemies.
The Energy Department has released millions of Cold War documents over the past six years. Now the Clinton administration has decided to put the brakes on its declassification program.
Â"I am slowing down the declassification process so that we can go back into the files and the archives to make sure nothing we are declassifying hurts our national security with nuclear weapons design or anything else,Â" said Energy Secretary Bill Richardson.
It was former Energy Secretary Hazel O'Leary who carried out the Clinton administration mandate for openness.
The policy change comes amid growing evidence that some of America's fiercest adversaries didn't even have to steal nuclear know-how. The U.S. gave it to them.
Former UN weapons inspector David Kay says the large-scale declassification is a blunder that will be felt for years to come.
Â"It was wrong. It was really dangerous, and that danger is going to come home to bite us in the future,Â" Kay said.
Now, under orders from the White House, the Energy Department is doing what many say should have been done in the first place - promising that not a single page of classified material will be released until it is examined and assessed.
The Energy Department has already been embarrassed by the apparent theft of U.S. nuclear secrets by China and reports of lax security at U.S. weapons labs.
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