Let's face it; you can make all the preparations you want, and
you will never be able to cover for every single contingency. I'm
not saying that the Government is not preparing for terrorist
strikes; what I'm saying is that you simply can't cover all your
bases.
If the recent terrorist strikes are of any indication, terrorists
are no longer so squemish about going for 'soft' targets of which
there are a lot. Terrorists would of course want to strike directly
at what they perceive to be the 'main enemy', which is the
government or the military.
On the other hand, the Madrid, London and most recently, Mumbai
bombings all went for purely civillian targets with the intent to
cause the maximum number of civillian casualties. The Mumbai
bombings, for instance, were timed such that they occurred during
the evening rush hour. You would of course want to impose tight
security on government buildings and military installations, but
there's no way you could do the same for every single HDB
block.
Of course, we try to learn and adapt to the changing tactics of the
terrorists. For instance, after the Madrid bombings security at MRT
stations was beefed up. But the MRT represents only one potential
'soft' target - there are many others out there as well.
Heck, when I sit down for lectures with 300-400 other undergrads I
sometimes can't help but wonder about what would happen should a
bomb go off in the lecture theater. 
I guess the only feasible defence against strikes on soft targets
would be public education, namely, to have the people on the
lookout for any suspicious activities. But right now I'm a bit
sceptical of that as well, considering the apathy of the general
populace in such matters.
