The Virginia Tech massacre has spawned countless questions: Everything from why would student Cho Seung-hui gun down 32 fellow human beings, to why was campus security not able to prevent him from committing the deadliest mass-shooting in U.S. history.

Three of the questions – all related – posed to me have been: Why didn’t some of the students rush Cho? Why didn’t someone tackle and disarm him? Where were the likes of those brave souls of United Flight 93 who made the decision to “Let’s Roll” on September 11, 2001?

First, to the third question: The brave souls were there at Virginia Tech, and they rose to the occasion on April 16, 2007. But like those of Flight 93, bravery wasn’t enough.

Now to the first two questions: It’s easy to Monday-morning quarterback about what any one of us would have done in similar circumstances. It amazes me the number of people who have told me, they “would have rushed Cho.” And they “would not have just sat there and let him do what he did.”

But make no mistake, no one really knows what they will do under fire, until they are in fact under fire. And like all combat actions, there are tactical variables at play that often carry more weight than any combination of courage, quickness, and reason ever will. Not that C,Q, and R don’t matter: They do, and lives are nearly always saved because of them. But they are usually not enough to save everyone in the face of a determined killer or killers.

Let’s consider a few of those tactical variables in the case of the Virginia Tech massacre.

Aside from being armed with two (easily reloadable) semi-automatic pistols with plenty of ammunition, the shooter, Cho, had countless advantages as he entered each classroom:

1) Cho possessed the elements of both surprise and shock: The latter includes terror, which can in many instances physically, mentally, and emotionally paralyze the victims.

2) Cho was in close-enough quarters – with few exits – that his victims would have found it extremely difficult to escape: In fact, he was – in many cases – positioned in front of the only door in a given classroom.

3) In almost every classroom, Cho’s field of fire would have been between 45 and 90-degree angles, affording him complete coverage of every space in the room at any one moment.

4) Cho’s victims would have had no cover (physical protection from Cho’s bullets) and virtually no concealment at any time during the attack.

5) The small, terrible space between the doorway - which Cho would have entered with guns blazing – and the groupings of desks where the victims would have been sitting, would have been the deadliest space in the room. For a student to rush Cho, the student would have had to immediately overcome the shock of the attack, unhesitatingly bolt from his or her desk, and charge exposed and unarmed directly across the deadliest space in the room to the source of the killings. This would have been a wholly unnatural act for anyone (I’ll explain this in a moment), yet we may never know if one or two victims actually did do this.

6) The charging, unarmed student would have had no way of knowing whether or not there were more unseen gunmen following behind the visible shooter, Cho.

7) Cho was a fanatic, and prepared to die in his own attack. Continued...