The most famous question in philosophy asks if a tree falls in the forest and no one is around to hear it, does it make a sound. I can’t answer that question for you, although I believe that here on planet Earth there is always something around to hear. I do know with certainty, however, that acts of terrorism are committed more for the reaction they induce than for the carnage they create. When it comes to terrorism, it’s not essential that any carnage is actually created. The point is to create fear which then causes the fearful to respond in a fearful manner.
So, if a terrorist plot fails to create any carnage, about the stupidest thing you can do is to freak out about it. If you freak out, you can easily turn their failure into a success. I want Joe Lieberman to read this repeatedly until he understands it.