That is all just my hypothesis, I am not saying that is how it happened, I am just guesstimating, based on my scant knowledge of previous such acts, that the bomber(s) in this instance was or were poorly trained in what he, she or they set out to do. I shudder to think about the outcome had the guilty person(s)
been well trained, previously experienced, and sufficiently equipped terrorists.
Edited, on 04/16, to add: I want to be absolutely clear on this, I am not trying to belittle the loss of any victim's life or the horrid injuries that many people suffered by saying that I believe whoever did this was amateurish. Because I think the bomber(s) was probably inexperienced does not make the act that was committed any less a terrorist act. Regardless of the level of expertise of the bomber, the outcome was terrifying. Even one injury was too many; yet, whoever did this injured scores of people and killed others. The injuries sustained by people were horrific, that is certain. The loss of life definitely most terrible and saddening. The emotional injuries and scarring, to they who lost loved ones or had loved ones injured or who were injured but survived, unendurable yet long lasting. The disregard shown by the bomber(s) for the victims is unfathomable but worthy of every effort to understand it so to be better able to hunt down the killers and swiftly bring them to justice. As I said in my earlier post about the bombing, I am keeping all of the victims and their loved ones in my thoughts and prayers and I mean that most sincerely.
All the best,