Prior to 1968, pilots were not searched or grilled prior to taking command of the aircraft they were scheduled to fly. They were also allowed, and sometimes required(Postal regulations) to carry a handgun. Most just carried a small .38, no training program, it was just assumed any grown man could do what was simply required and they did.

Then came the crime of aircraft hijacking, mostly just by fruitcakes wanting to participate in the then current fad of Cuba.

Then came cooperation with criminals and lunatics as a policy.

The result was that many aircraft were destroyed and people murdered over the years culminating in the mass murder of 3,000 or so people.

Progress is not always forward and upward.