Hijackings were pretty much a daily thing (or three times daily thing) for decades.
Although until 9/11 the intent usually was either to get to a non extradition country, or demand something from some nation state primarily.
The source above shows a clear decrease in airline fatalities through the years but I suspect that’s due more safety improvements through autopilots, better sensors, and more redundancy than the decrease in hijackings.
You are vastly over-exaggerating. According to https://aviation-safety.net/statistics/period/stats.php?cat=... , even when limiting to the period between ~1970 and ~2003, it is about 2 per month on average. The total sum of fatalities is just over 1000 people.
This is nothing to justify the massive surveillance.
Although until 9/11 the intent usually was either to get to a non extradition country, or demand something from some nation state primarily.
The source above shows a clear decrease in airline fatalities through the years but I suspect that’s due more safety improvements through autopilots, better sensors, and more redundancy than the decrease in hijackings.