According to a Rand report http://www.rand.org/pubs/monograph_reports/MR989/MR989.chap2.pdf some of the most serious terrorist attacks have not been credibly claimed.
As for the why of terrorism, one has to include the terrorist’s desire to create multiple scenarios that would cause law abiding, peaceful citizens to question the trust they place in their government to provide that protection.
That kind of doubt on a national level could present an opportunity for a larger, more encompassing authority to step into the manufactured void and offer a conditional security.
Now, who would want to see that happen? Common sense should tell us that only a small group in a concentrated circle of power could pull that off and this past November provided ample evidence of their reach.
Hacking into anywhere should be a piece of cake for such a group.
Even in that case, I don’t think this is likely to be terrorism. The object of terrorism is to cause terror... think of the swine flu, which has killed two people in this country, and the Air France crash, or any non-terrorist crash which has killed hundreds. Regardless of the death tolls, people seemed more scared of flying not because there might be a mechanical or electronic glitch that could bring down the plane and kill them, but because another passenger might have a disease that probably wouldn’t kill them. And questioning trust in the government? When a plane goes down, people question their trust in the mechanics and pilots, but when several thousand people in Mexico come down with a new flu strain, they’re panicked because our government hasn’t stockpiled enough medications for the entire population and can’t come up with a vaccine ‘fast enough’ for everyone to get vaccinated.
Now, I’m not saying this wasn’t terrorism, or that the swine flu was. But, what I’m saying is why go to the trouble of doing something extremely difficult and complicated and relatively ineffective that would likely require someone outside their ‘circle of power’ (hacking like that is NOT a ‘piece of cake’ for anyone, not even the best hackers) when they could point the media hype machine wherever they want in their sleep and have all the desired results? If they wanted us to mistrust our government over flights that crashed for plausible reasons, we’d already be hearing nothing on the news except how some corrupt (and probably Republican/capitalist, too) American official was somehow responsible for whatever hardware or software issue that brought down this plane...