On June 10, 2013, Sen. Dianne Feinstein (D., Calif.), the head of the Senate Intelligence Committee, described Mr. Snowden’s theft of documents as “an act of treason.” A former member of President Obama’s cabinet went even further, suggesting to me off the record in March this year that there are only three possible explanations for the Snowden heist: 1) It was a Russian espionage operation; 2) It was a Chinese espionage operation, or 3) It was a joint Sino-Russian operation.

Mr. Snowden’s critics regard the whistleblowing narrative as at best incomplete, at worst fodder for the naïve. They do not believe that it explains the unprecedented size and complexity of the penetration of NSA files and records. For one thing, many of his critics have intelligence clearance. They have been privy to the results of an NSA investigation that established the chronology of the copying of 1.7 million documents that were stolen from the Signals Intelligence Center in Hawaii. The documents were taken from at least 24 supersecret compartments that stored them on computers, each of which required a password that a perpetrator had to steal or borrow, or forge an encryption key to bypass.

Once Mr. Snowden breached security at the Hawaii facility, in mid-April of 2013, he planted robotic programs called “spiders” to “scrape” specifically targeted documents. According to Gen. Dempsey, “The vast majority of those [stolen documents] were related to our military capabilities, operations, tactics, techniques and procedures.”