"While this is all very sad, and regrettable, I wonder, why all the fuss?"

It's because we have engendered in the US a culture of violence which spills over to
terrorist activities. The guns on the street have a correlation with the bombing incidents because it has become permissible to accept violence as something that no one can do anything about. It's a religious dictum that has to do with the "depravity of man".

If war is inevitable, it follows that violence is considered a human proclivity that is inherent.

I wholeheartedly disagree with this view. Until the culture of violence is rejected, there will be further unnecessary incidents like Boston. To cliche it: "We are better than this".