Maybe the response was a tad harsh, but I have to agree with the sentiment.
Agreed, and it was the way it was responded that irked me. No, by no means is this the ONLY thing they are looking at. But it is one of many ways you profile.
Your point is interesting though as it could apply if it was a well thought out planned attack. It definitely could have been a well thought out coordinated terrorist like attack. It just as easily could have been a lone wolf attacker who didn't put much as much thought/planning in to it. At this point both are very plausible.