The first time I heard the term trigger with regards to mental health I was dormed up with a young soldier at a mental health facility.
Dude said something about my behaviors or whatever was triggering him. I don’t remember what or what, I was HIGHLY medicated. But what I do recall that triggering and triggers was language used by a number of those soldiers dealing with PTSD and the like. It was a way for them to understand and communicate what they were experiencing while working towards a better life.

It was about three - four years between then and when I heard that term again. And this time it become a derisive punchline
“OMG so triggered”
“Triggering the libs/sjws”
And the lot
Most recently I read it yesterday. Some dude running for something failing against safe spaces and trigger warnings and I feel bad each time I see this tone.

That a language that was so helpful to so many that I met has become so stigmatized and weaponized. We’re going on what 17/18 years since we invaded Iraq and Afghanistan with no end in sight and the space to really deal with the trauma of that has considerably shrunk.

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“There is no fate that cannot be surmounted by scorn.” -Albert Camus