It is true, however, that the military has strict rules for when lethal force are permitted. I'm not sure how that counters anything said here, since LE also has very strict rules.
In hindsight, we can all examine the facts and agree the force used in that situation was unwarranted. But that's the benefit of hindsight.
Regardless, we should not focus on how many rounds were fired. We should instead focus on how the wrong decision was made in the first place.
That is the point of this entire thread. Do not use round count to indicate anything. It just doesn't indicate anything...