Im going to chat with you as you provide a much more balanced arguement than personal-attack-know-it-all i have been talking with.

Yes, the call was ambiguous and easily debatable at the time - no disaster is ever one mistake and unfortunately in this case everyone paid for it with their life, including the ATC controller.

The TCAS was designed and taught as a last resort option, and was to be followed instantly and overruled everything, including ATC. Unfortunately it only works if everyone follows it - one did, one followed atc and they dived into eachother. The system failed because it wasn't followed, and at the end of the day the pilots knew that TCAS took priority. The pilots are in final command and responsible for their aircraft, and cant blame anyone else who gave instructions anymore than the holder of a firearm, captain of a ship or driver of a vehicle.

Modern understanding adds a number if factors into play, namely peoples reaction to authority in an emergency. Pilot error caused the crash, but there are multiple factors that went into their error - external authority (who pilots are used to listening to), sudden need to react in an uneventful flight, cant remember if there were training, equipment and fatigue issues or not, and a pile of others. No one reacted recklessly (don't know why other poster thought I said that), just instantly with no chance to second guess their choice.