The surveillance machine grew too big for anyone to understand.
The National Security Agency set it in motion in 2006 and the vast network of supercomputers, switches and wiretaps began gathering Americans' phone and Internet records by the millions, looking for signs of terrorism.
But every day, NSA analysts snooped on more American phone records than they were allowed to. Some officials searched databases of phone records without even realizing it. Others shared the results of their searches with people who weren't authorized to see them.
It took nearly three years before the government figured out that so much had gone wrong. It took even longer to figure out why.
Newly declassified documents released Tuesday tell a story of a surveillance apparatus so unwieldy and complex that nobody fully comprehended it, even as the government pointed it at the American people in the name of protecting them.
A raid by federal immigration authorities on Saturday in New York City was thwarted by about...
