Schneider said Sheehan had worn a T-shirt with an anti-war slogan to the speech and covered it up until she took her seat. Police warned her that such displays were not allowed, but she did not respond, the spokeswoman said. (LA Times, Google News Search)

So now you can be arrested, in the capital (and Capitol) of the United States of America, for wearing a T-shirt with an anti-war slogan. She was arrested under the charge of “campaigning in the Capitol building”.

Explain to me which “political campaign” peace is part of?