I personally don't feel it's a question of left or right in regard to political perspective, or what someone's religious belief or non-belief is. I feel it's more a question of right and wrong, and most of us know the definition of right and wrong when confronted by it without the need for a political or religious foundation.
It is wrong to deliberately target civilians in an attempt to further your aims whatever those aims are? Whoever you are, be it government, individual or organization.
I remain absolutely astounded that the entire of Boston was "shut down" due to the pursuit of one individual? I know that many posting here have differing personal definitions of what terrorism is and exactly what it constitutes and encompasses. But the official US government line on this includes: "to intimidate or coerce a civilian population; to influence the policy of a government by intimidation or coercion". It seems to me that this was achieved (short term) via local government and national and local law enforcement decisions on the day.
I just hope that others intent on this course of action in a twisted attempt to further their particular aims don't see this as a potential "new tool" in their arsenal. One man shutting down a city with all its inherent cost both in terms of liberty and economics.
If someone had told me last week that an individual on foot, on the run with some IED's could do that to a city of that size and population I would have laughed at them.