Naturally, we can only condemn in the strongest possible terms the people responsible for the bombs in Boston on Monday. The design of the attack was cruel and cowardly, suitable only for terrorizing. The attackers will be caught, and while the justice imposed on them will be severe, it will not be nearly as bad as what they deserve.
Why do I feel so strongly they will be caught? Two or three things. First, while I would not call the US a "police state", it is a very well-policed one. We have an over-abundance of police at all levels (the Federal ones a bit less visible). This kind of stuff is now firmly, deeply ingrained in our national culture: the number of shows about law'n'order generally, and Crime Scene Investigation in particular, has mushroomed beyond all reasonable bounds. In the specific case of Boston, recall the recent movies "The Town" and "The Departed", which had the multiplicity of cops of all kinds as a theme in each. All of these are very eager to put to work their detective skills and criminal forensics capabilities. Any physical evidence at the scene will be collected, documented, analyzed, and correlated.
Then, there's the fact that the plotters, no doubt in order to create the greatest shock on the public psyche, chose to set off the bombs in one of the most public, most camera-covered places imaginable. There were dozens, if not hundreds, of cameras trained on the area at all times. Whatever precautions those who set the bombs in place may have taken, there will be a variety of still and action shots taken of them, from a variety of angles. Their 'tells' will be spotted, and the descriptions of those most visible will be produced. We can then hope that tracking down that person/those folks will lead to all the cell membership and it will be broken.
This is a good thing, that a public place should be so heavily covered with cameras. It is important to make a clear distinction between the public spaces, subject at all times to closed-circuit monitoring with review by any and all agencies, and private spaces, in which privacy must be possible and any monitoring is under the control of the right private individuals. The inside of my house is off-limits to the snoops; the outside, too, though I am responsible for anything that comes out of my property into the public space. My car is private on my property, but not when it's out on the public thoroughfares. My computer is private, but what I put out there is not. These are rules that our public agencies, our courts, and our journalists, need to respect.