"This" was the 355th mass shooting in America this year alone.

My husband nodded. "I already did." He'd had a day off from work, and like most of us in America, he'd kept the news on all afternoon, desperate for bits of information out of San Bernardino, hoping against hope that the shooters were caught, that the situation was under control. When he went to pick our daughter up from her after-school program, he'd kept the news on... and a conversation was inevitable.

I wasn't surprised.

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We used to hide mass shootings from our daughter, trying to protect her innocence, trying to make sure she feels safe. When a gunman walked into Sandy Hook Elementary School in December 2012, we opted to keep our television dark, our conversations limited to desperate whispers behind closed doors. When a Navy subcontractor opened fire on the Washington Navy Yard in September 2013, we drew information only from our phones, hidden away from her curious eyes and ears.

Quiet desperation was our modus operandi.

We can't be quiet anymore.

Certainly her age plays a role: At 10, she's able to handle much deeper, more devastating news than she could just a year or two ago.

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Still, she's only 10. She's supposed to be playing with LEGO bricks, not pondering a world where people destroy dozens of lives in a single afternoon. If I could allow her childhood to remain unstained by moments of pure terror, I would.

But I can't. I can't because there have been 355 mass shootings in America already this year. I can't because she's being raised in a world where emergency fire drills have been replaced by active shooter drills in our schools, a world where little boys and little girls climb into school buses in the morning and never return home.

We talk to our daughter about mass shootings not because we want to but because we have to.

This is the world in which she's being raised. She needs to know what to do if she sees someone with a gun in her school, in her movie theater, in her mall.

She needs to know there are bad people in this world.

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She needs to know to stand up, to fight for all that is right and good and pure in this world.

She needs to know that Edmund Burke was right: The only thing necessary for the triumph of evil is for good men to do nothing.

We can't hide mass shootings from our kids if we want them to be the good men of the future. They need to know now what it is that can happen in a society where people rail against violence when it occurs, only to forget when the last funeral song is sung and a celebrity's ridiculous antics have pushed the stories of the victims off the front pages.

Because soon enough it will be up to them to stand up and say, "Not one more."