Considering the bumper sticker below, spotted in Ithaca, a little history lesson is in order:

The Saint Patrick’s Day Four (also, The Saint Patrick’s Four, or SP4) are four American peace activists of Irish Catholic heritage who poured their own blood on the walls, posters, windows, and a US flag at a military recruiting center to protest the United States’ impending invasion of Iraq. The four consisted of a Vietnam War Veteran, former Binghamton City Mayor John Burns’ son, and two sisters. Peter De Mott, Daniel Burns, and Teresa and Clare Grady each are members of the Ithaca Catholic Worker community, which teaches that Christians should practice non-violence and devote their lives to service of others. They each served between four and six months in federal prison for their action on Saint Patrick’s Day, March 17, 2003, in Lansing, New York, near Ithaca where they reside.

The group’s support website now is defunct, but partially available at WaybackMachine (this page from 2007 shows the trial results and sentences).