Is a lack of success with girls/sexuality a major cause for mass shootings?

[President Punxsutawney Phil]

Perhaps it's a factor, but I doubt it's the primary cause.  Many people have this lack of success but are sane enough to realize that's no reason to go out and murder people.

This applies to most of the 'reasons' mass shooters usually have for committing their crimes, though.
For instance, in the 1998 shooting, the two shooters were bullied and isolated. Millions of kids have been bullied and isolated. The vast, vast, vast majority have not then committed mass shootings.

Look at social trust levels. Higher social trust means that generally people feel less need to own guns, and reduces the level of people who are potential mass shooters too.
There's a reason social trust levels declining over the past (40?) years also has paralleled an increase in gun violence.

[President Punxsutawney Phil]

Look at social trust levels. Higher social trust means that generally people feel less need to own guns, and reduces the level of people who are potential mass shooters too.
There's a reason social trust levels declining over the past (40?) years also has paralleled an increase in gun violence.

but gun violence peaked in the 90s and went way down for most of the next two decades, has "social trust" (whatever the hell that means) been going up since then?

Which statistics are you looking at? I'm curious, I had the impression they were going up overall.

[President Punxsutawney Phil]

Look at social trust levels. Higher social trust means that generally people feel less need to own guns, and reduces the level of people who are potential mass shooters too.
There's a reason social trust levels declining over the past (40?) years also has paralleled an increase in gun violence.

but gun violence peaked in the 90s and went way down for most of the next two decades, has "social trust" (whatever the hell that means) been going up since then?

Which statistics are you looking at? I'm curious, I had the impression they were going up overall.

Thanks for this graph.
I guess, as it is, gun deaths going down does not necessarily mean higher social trust levels, and gun deaths going up does not necessarily mean social trust is going down. The latter is just one of multiple factors, but it's important as a background factor to a number of phenomena that also add to gun violence.

As for the definition of "social trust", here is what I came across on Google:
"Social trust is the confidence that other people will do what they ought to do most of the time." - Atlantic
"Social trust is a belief in the honesty, integrity and reliability of others – a “faith in people.”"- Pew Research
"Social trust is a perception in the honesty, integrity and reliability of others — a “faith in a human being.” - Medium

I apologize if this is too esoteric or pyschology-sounding. I remember the 538 podcast talking about it in relation to polling responses and all that, affecting how likely someone is likely to respond to a pollster.