Most big fish are overseas, I hope. If I recall, the way they blew that big fish up in Yemen with a hellfire missile was because he called here and got tracked.
I hope you don't think every arrest of a terrorist here, especially a non citizen, is being reported. In fact, I'm guessing a few foriegn nationals have just vanished. As it should be.
No, I don't think it is all being officially reported, or should be. But things happen when folks are being arrested that don't escape notice. Like when you heard a bunch of noise last night, and walk out into the hall of your apartment building and note that the door down the hall has been smashed to splinters. And then you notice that you don't ever see that guy around anymore.