Verified Defense Pro
As I noted on Twitter, around $190 bn/yr. Spread over mostly a few departments, and while it's not quite budget dust, it's not that far off, even limiting ourselves to just discretionary spending.Some sobering numbers on the cost of US counter terrorism measures for the last 15 years.
Here’s how much the US has spent fighting terrorism since 9/11
Additionally, while saying we've only had about 6 killed a year by jihadi/Islamist-inspired attacks) sounds damning, if one remembers that the entire point was to fight the extremists on their own shores and not play defense. Also ignores how many have been arrested pre-attack (although IMHO I'm not sure how good a metric that really is anyway).
TLDR article has a big number, but can't answer (and doesn't try to raise) question of "Is it worth it?"