(CBS News) JANESVILLE, Wis. - Fourteen Roman Catholic nuns on a nine-state bus tour are in Chicago Wednesday, after several stops in Wisconsin. Officially, they're protesting cuts in federal programs for the poor. But the "Nuns on the Bus" tour is also an act of defiance against criticism from the Vatican.
Sister Simone Campbell is a Roman Catholic nun and the executive director of Network -- a liberal social justice lobby in Washington.
She's been under siege, but she's not fazed.
"Into every life a little rain must come," she said.
Sister Simone is also a bit of a provocateur.
"Catholic sisters have always been out on the edge," she said. "And quite frankly we have a long history of kind of annoying the central authority."
The central authority they've recently annoyed is the Vatican itself. In April, sister Simone's group and the Leadership Conference of Women Religious -- representing 80 percent of the nation's nuns -- were attacked by the church hierarchy for focusing too much of their work on poverty and economic justice, while being silent on abortion and same-sex marriage.
Simone says she pleads guilty to part of that charge: "That I spend too much time working for people in poverty. I wear that as a badge of honor."
The Vatican has appointed a bishop to correct what the church calls "serious doctrinal problems" in the way the nuns work.
They've been called radical feminists.
Simone's response: "Oh my heavens. I actually have to laugh. We are strong women. We're educated women. We ask questions. We engage in dialogue. That's all we do. We stay faithful to the gospel and trying to live it.
"But in living it, you break it open and ask questions," she said. "It's fabulous."
So Sister Simone has doubled down -- launching this bus tour in what can only be seen as a retort to Rome.
The sisters are focusing on social issues all along the way -- holding press conferences and staging protests against the proposed budget cuts which they say will endanger those most in need. At the starting line in Iowa, there was no talk of same-sex marriage.
"The truth is we have to speak up for the people who are suffering in our society," Simone said. "That's our mission. That's our goal. That's what Jesus would do. That's the gospel."
And off they went -- the Daughters of Charity, the Sisters of Mercy and others -- barreling down the back roads -- and not slowing down.