When I sit down on the subway platform, the tears begin. My wrists have deep marks from the handcuffs, but my tears are for my daughter. This is her first day of kindergarten, her first step into that wider world, where she will discover her own voice. And I am not there. I am here, rubbing my wrists, waiting for a train to take me away from this Washington, D.C., police station. This is not the type of mothering I want to do.

As my "baby" walked into her first day of school, I was sitting in front of the White House, waiting to be arrested. Because as much as I wish things were different, I couldn't feel good about being the kind of mom I thought I was. Mothering, in this century, means carrying the grief of dire possibilities around with you. And doing everything you can to fix a broken system.

My mothering work is to look clearly at how our climate is changing now. To stay sane, I must choose: denial or hope. I choose hope, in the form of these bruises on my wrists, in order to urge President Obama to protect the planet my children have to live on. Obama can deny the permits for the Keystone XL pipeline to be built; alone, he can stop an environmental disaster.

If built, the pipeline will carry tar sands from Canada to Texas oil refineries, escalating the rate at which the carbon in the tar sands is released into our atmosphere. Leading scientists say that if we release this carbon, it will be "game over" for our climate. Which means that my kids will be trying to live on a dying planet. President Obama can, and must, say no.

Before I left, I looked at my daughter. "I'm gonna miss you, sweetie. I hope you have a great first day of kindergarten."

She pondered me, smiling. "I hope you have a great first day of going to jail, Mama."

And so we both step out into the world. May our voices carry.

Kenna Lee is a Sebastopol mother of three, hospice nurse and writer (www.milliontinythings.com). She hopes you will sign the online petition opposing the pipeline at www.tarsandsaction.org.

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