The religious wars in Europe in the 16th and 17th Centuries burned themselves out. The wave of anarchist bombings and assassinations at the end of the 19th and the beginning of the 20th Century that resembled the events of the past year eventually died out. While Iran certainly continues to present problems, it is no longer the Islamic revolutionary state that it was in 1979; it is simply a conventional state pursuing its own interests in the Middle East, just like all of the others.
We will ultimately prevail over this menace. It will take time and patience and discipline and carefully directed force, but we will win, because the terrorists have nothing worthwhile to offer as an alternative.
In the meantime, there are no quick and easy answers, so don’t be disappointed if you don’t hear any in the next few days. Show your disgust by all means, but overreacting and searching for scapegoats is counterproductive.