When he addressed the nation earlier this week, President Obama highlighted the fact that each year, more than 30,000 Americans have their lives cut by gun violence.

More so than any other developed nation.

So why does it happen here? And so frequently?

There is no easy answer to this, but perhaps we can learn a bit more about why by looking to our past - especially the history of Southern California.

That's just what writer Hector Tobar has done in an op-ed published by the New York Times.