They already do this. If a passenger appears to be drunk before boarding the plane, they can refuse to let him board. No big deal.
Even better than this is adding full-body scans (without those stupid metal modesty shields for crotches) and those "puffy" machines that detect the odors of explosives to the security protocol.
Profiling is good, but not foolproof. Eventually an 18-year-old squeaky clean white American cheerleader is going to show up packing explosives somewhere on her nubile and amazingly limber young body.
Actually, in this instance I imagine the cheerleader would get the extra thorough body scan even if she passed the profile.