There have always been accidents in the air. Travellers have come to live with these odds, especially when they understand the overall safety record of air travel as opposed to just getting in your car and driving to the mall. Most of us find this risk acceptable.
If, however 587 and 800 were even randomly targeted by terrorists and the Feds admit so, then they must also admit, at least tacitly, that they cannot make air travel safe. This would cripple multiple economic segments.
It is interesting to note that in the days leading up to the Flt 587 downing Ridge was all over the tube telling us to be extra vigilant, something is coming. Well, something did come and within hours they were assuring us that it was nothing more than a tragic accident.
Also interesing is the lack of an order from the feds grounding every one of the hundreds of other Airbus 300s in active service in the US. If, as they want us to believe, the crash was due to some structural problem then it would be reckless in the extreme not to keep the rest of them on the tarmac. Remember, after the Concorde crash it was a year before another one took off.