The phrase "senseless tragedy" refers to a situation or event that is very sad and unnecessary, with no clear reason or logic behind it. Full definition
«I wanted to walk in memory of Angela and to help prevent this kind of senseless tragedy from happening to other women and families.» (remonline.com)
I am sure we all have the recent senseless tragedy at Marjory Stoneman Douglas High School in our minds. (morrisjeffschool.org)
From the desk of Patricia Perkins, Principal: I am sure we all have the recent senseless tragedy at Marjory Stoneman Douglas High School in our minds. (morrisjeffschool.org)