Last month, The Washington Post published details of the nation’s top-secret intelligence budget, based on documents provided by former intelligence contractor Edward Snowden. The documents show that, for the current fiscal year that ends Sept. 30, the intelligence community requested a total of $52.6 billion, with $16.6 billion (31.6%) of that designated for counter-terrorism efforts. In fiscal year 2012, the United States spent $17.25 billion on counter-terrorism.

Since the terrorist attacks on Sept. 11, 2001, the United States has spent more than $500 billion on intelligence, according to The Post. The 2013 budget request was about twice the size of the estimated 2001 budget (in constant dollars), the paper said.

In terms of money spent, monitoring and disrupting violent extremists and suspected terrorist groups is the intelligence community’s second-biggest mission objective, after warning U.S. leaders about economic instability, societal unrest and other critical events around the world (which takes about $20 billion). Other priorities include preventing the spread of weapons of mass destruction, protecting U.S. computer networks and defending against foreign espionage.

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