It began as a ride to work, and ended up as a commuter's worst nightmare.

Last Tuesday, as Philadelphians sped through the rush hour in the usual morning routine, 36-year-old Eileen McGuigan rode along with her fiance, discussing wedding plans.

A few minutes later, another driver cut them off, prompting a few choice words and a raised middle finger. Happens every day, right?

But suddenly, the mother of four was dead, after the driver who cut them off pulled over, stuck his arm out the window and shot Eileen McGuigan in the right side of the head.

Even in a city growing increasingly accustomed to random, irrational violence, the Schuylkill Expressway shooting was shocking, inexplicable. But it is becoming more and more common. A few weeks ago, a young woman who reportedly was a murder witness, was shot dead as she worked at her desk at a downtown Philadelphia law firm.

A question that springs to mind after such senseless crimes is "What kind of person could do that?" Once upon a time, the explanations about how people are products of their environments held up. They sounded rational enough: That a person who grows up in the ghetto believing they're worth nothing as a human being can't be expected to have any value for human life. But as America's cities get increasingly more violent, those excuses dry up.

What degree of poverty or drug addiction or broken homes makes someone a "product of the inner city"? The fact is, it comes down to a basic human knowledge about right and wrong. It shouldn't take very much to teach a person that it is wrong to kill another human being, that getting pissed off because someone gave you the finger doesn't give you the right to take their life.

While the reasoning may explain why some of the crimes happen, they sure don't excuse it. Defense attorneys and bureaucrats are quick to trot out statistics and stories about inner-city youths growing up watching the drug dealers with 9mm guns getting respect. They become role models, and killing becomes a way to get respect.

But that excuse doesn't always work.

Tony Smallwood, a 41-year-old bus driver from the Nicetown section of the city -- hardly the ghetto -- was arrested and charged with Eileen McGuigan's murder. Smallwood had recently been fired from his job at Bryn Mawr College and had a prior police record including murder charges. Police tracked him down after another driver gave police his license plate number.

Ed Connor moved to Centre County from Philadelphia a few years ago. He didn't move here because the taxes were too high or because he was offered a better job. He moved after he was shot in the line of duty as a Philadelphia police officer.

Connor said goodbye to his hometown after being hit during the 1985 MOVE confrontation. He's now the Ferguson Township Police Chief.

He doesn't intend to go back. I do.

"What kind of person could do such a thing?"

I had hoped that through writing this column I could find an anwer to that question. I'm becoming convinced that there is no answer, no rationalization, and no way to numb yourself from the horror. I can't bring myself to accept the inner-city drug culture rationalizations.

It scares me not to be able to answer the question. Things would be easy if there were someone to blame, a "kind" of person we could pin all of our problems on, because undoubtedly it wouldn't be anyone like us, certainly not anyone we know. But our naivete makes us all accountable. We're all to blame, and we're all at risk.

A friend told me recently I sounded like someone who used to be a liberal but now can't accept the bleeding-heart sentiments. Being here in State College for the last three years has made me more acutely aware -- more jaded, maybe -- of the changes taking place in the city I love so much. Actually I think I'm even more cynical after leaving the city than I would be if I had never left.

Here, where an armed robbery makes front-page news, there is a feeling of shelter, of being protected from the big bad world, because of course, nothing like that could happen here.

But it can, it does. The day I returned from Christmas break, the big local news was about an elderly man who allegedly stabbed his wife to death. It is becoming impossible to get away from the violence, and impossible to get used to.