What is an example of a collectively traumatic event? How do you see the effects of this collective traumatization playing out today?

http://time.com/4672257/ashton-kutcher-human-trafficking-speech/?iid=sr-link1
i saw this video then decide to write about human trafficking. might require extra research. i wrote a little bit myself (the document is called ispf)

while your arguing human trafficking is a collective traumatic event and how it is playing out today, maybe you can use some of my teacher’s research to strengthen your claim.
the research is attached