In an article about a couple of bomb scares in NY, there was this:
One jihadist activist monitored by the private SITE Intelligence Group suggested to others online that they call in bogus bomb threats to the police or media offices.
The activist, a member of the Shumukh al-Islam forum, said "they will consider every communication such as this as a real report, for they are cowards and they fear that all reports are true," SITE reported.
http://www.calgaryherald.com/news/Bomb+scares+cause+York+jitters/4003228/story.html
So true. All they need do from now on is bark. No bite needed, with the exception of a couple of amatureish, fumbled (by design?) attempts like the shoe bomber or underwear bomber. It's a sad truth and those who cower under their beds like most conservatives are just the ones who enable them, along with the government who impliments expensive "security" proceedures/equipment to appease the fearful.
IMO, if any terrorist organization wants to do real damage, nothing that has been put into place can stop them. It was their intention to cripple the US economically. Again, my opinion.