Is any death meaningful?

Many times the phrase let their deaths not be in vain has been uttered like at moments of civil strife and I am here asking myself, if deep down these deaths were meaningless. Did someone have to die for something to be achieved?

Take for example the over 30 people who were killed by police in our last election. What did they die for? What, if you were to meet their parents or relatives, would you tell them was achieved by their deaths?

In the movie silence, based on the Japanese inquisition of the 16th century (2016) by Scorsese, a number of Japanese endure torture and some even die to show their faith in Jesus. Was this rational? What was the point?