Demonstrators protesting Line 3, a proposed pipeline expansion from Canada to Wisconsin, march Monday in D.C. (Ricky Carioti/The Washington Post)

Gina Peltier prayed over the Mississippi River earlier this month, hoping that President Biden would step in to stop the oil pipeline that she says will threaten Minnesota lakes, wild-rice waters and treaty-protected tribal land.

Now, in the nation’s capital, she was joining more than 100 people in chanting for his administration to cancel the federal permit that allowed this “black snake” of a pipeline expansion called Line 3.