“From fiscal 2002 to 2017, the U.S. spent 16 percent of its entire discretionary budget as part of the counterterrorism fight, a new report has found. Counterterrorism funding — a broad term that includes government-wide homeland security efforts, international funding programs, and the wars in Afghanistan, Iraq, and Syria — totaled $2.8 trillion between fiscal year 2002 and 2017, per the newly released Stimson Center study.”
Source: Here’s how much the US has spent fighting terrorism since 9/11