Boynton Beach is the next town over from where Mohammad Atta and crew practiced flying (Lantana Airport). Several hijackers rented hotel rooms and spent time in BB right before 9/11. Bob Stevens, the first victim of anthrax, resided in neighboring Lantana.
Also, and perhaps unrelated, many gang members live in the area of east Boynton Beach.
Boynton Beach is exactly what others have said...
..It's not a town that would call attention to itself..
...a sleepy beach town where 'middle eastern' types could be invisible, it attracts some tourists...retirees...
Another poster had a unique 'take' on this...
Terrorists using our evacuation routes to plan attacks.
Never thought of that one...
..and with hurricane season here....hmmm.