That's what makes it 2nd degree and not manslaughter. Manslaughter assumes that the death was the result of an act or action which was never intended to kill or to even bring about great bodily harm. It's also sometimes used when the death was the result of gross negligence.
That being said, I'm not so sure that charging him with 2nd degree murder was the best decision, since that would be much harder to convict on since you do have to establish intent, which is often so subjective as to be nearly impossible to nail down beyond a reasonable doubt.
Of course, it could also be the state would really like to avoid a trial altogether as so this might be a ploy to create a situation where it might be easier to get Zimmerman to plead-out thus avoiding all the publicity that a trial like this would create both for the State of Florida and for those groups who are defending these 'stand your ground' laws. A trial of this nature, considering the level of national media involvement already occurring, would not be to the advantage of either the state or the proponents of the law. This is a lose-lose situation for them. Even if Zimmerman managed to avoid conviction, the damage will have been done, so I suspect that all effort will now be put on getting this resolved ASAP, which can only happen if he takes a deal.
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