I suppose I could say I know quite a bit about UK prisons, having been inside eight of them, including two 'A' Cat ones. And it's true that prison officers have an awful time and earn every penny of their salaries. A surprising proportion of inmates have mental health problems, appalling backgrounds (abuse, neglect etc) and can be frighteningly violent.
I also have an innate feeling of pity and care about any human being on the 'wrong side' of society. After all, a baby is a blank canvas, and someone must have written bad things on it to make it an evil, dangerous person.
But we must protect society from danger. Paedophiles, terrorists, violent robbers and drug barons etc are totally toxic to us.

I often think of Dickens' quote from A Christmas Carol: (Scrooge) "Are there no prisons? And the Union workhouses?" There must surely be other solutions out there, but I can't for the life of me think what they might be.