The tragedy at Virgina Tech is something no rational person ever wants to see happen again. The calls for for securing University Campuses by locking them down are well intentioned but almost impossible to execute without totally rebuilding every university in the country to be fortresses. Imagine making all our universities look like Supermax Penitentiaries because that is the degree of security it will take to prevent tragedies like this from happening again.
Others promote stricter gun control as a solution, but all gun control does is put limits on law abiding people. Criminals will find ways to get guns or other weapons to use in their criminal activities. Consider the drug war as an example; if you control the flow of drugs like cocaine across the border users turn to drugs like meth which can be cooked up in someones home. Then limit the access to the items needed to make meth and users turn to huffing paint or other products to get their high. The same thing happens with guns. Limit legal access to guns, and the criminal finds illegal ways to obtain them. Limit legal caring of guns by legally licensed owners and you create a pool of easy victims for criminals to choose from.
Gun free zones have the opposite effect than is intended. Criminals who are intent on killing someone will not stop at the door and check their guns. Imagine if some of the faculty at VT had a weapon on them, the killer could have been stopped before he killed so many. VT could require faculty and students who which to carry take additional training above and beyond what is needed to qualify for a concealed weapons permit. Faculty who wish to have a weapon on their person on in the class room could even go through some of the same proficiency training and regular certification that the university police are expected to take and pass.
Ultimately the system failed. By reports I've seen the killer had been giving off signs that he was unstable and dangerous to himself and others. A court found him to be a danger and that finding was not on any criminal background search. It is exactly that kind of info that needs to be part of a criminal background. If his parents were concerned about him being suicidal as has also been reported they could have taken action to have him committed for his own safety. If other VT students made complaints about him the university could have acted to get him help or expel him.
Before we turn our universities into fortresses and or limit guns further we need to address the failings of the system first.