The recent leak of classified Pentagon documents has highlighted the vulnerability of the system which grants access to classified government information.

Initially suspected to have been an intelligence operation by a state actor, evidence is increasingly indicating that the leak originated from an individual working on a U.S. military base - motivated by impressing members of an online chat group.

As Statista's Martin Armstrong details below, the federal government grants top secret security clearance to large numbers of government employees and contractors: 1.25 million according to the latest publicly available figures.

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Speaking in Ireland on Thursday, President Biden spoke publicly for the first time on the issue, saying there was a "full-blown" investigation into the issue and that despite the potentially damaging nature of the leak, "“there’s nothing contemporaneous that I’m aware of that is of great consequence.”

The alleged leaker has been identified as 21-year-old National Guardsman Jack Teixera.