Your comment demonstrates how monumentally "The War on Terror" has failed, now that people have been so thoroughly terrorized that the most available explanation for a plane disappearing has become "terrorism".
That depends on how you view the war on terror. If you view it as political construct of Govts. wishing to grab extraordinary amounts of power and oversight over a largely disenfranchised populace then I would say it has been remarkably successful.
A large modern aircraft completely disappears suddenly, in good weather, without a trace. Terrorism could certainly be a logical explanation. It wouldn't be the first time. Mid-air collision, shot down, etc. The suddenness does raise extreme conclusions.
in this day and age? Sure. With the technology behind the newer planes flying to day it would take an extraordinary event to down one without word.
So the thoughts that come to me are, flew into terrain (mountain), door opened causing decompression and deformation of airframe, airframe failure, bomb, or someone took over fast enough to silence communications.
What is the availability of communications to passengers in that area? Cell has to be pretty much far between?
I don't think anybody can disable communications from inside the plane (but then, that's a guess, if anybody knows better, please tell so).
It would be compatible with some group kidnapping the plane, and changing the route to go over the ocean. But the plane would have already appeared somewhere, so I don't think that's likely.
Also, if it was a bomb, it would need to be quite a big one, to completely destroy the plane. Also unlikely.
He said it had a non-zero probability and should be considered, not that it was the most available explanation.
Considering that just a few days ago, China suffered a terrorist attack on a railway station by separatists that left nearly three dozen dead, it would certainly not be surprising to see an attack against an airplane flying to China and carrying a large number of Chinese passengers.