... a war protest. It was about women saying, "No, you cannot take this young man I spent 18 years teaching how to be a decent human being, and turn him into a monster, and then get him killed in your STUPID WAR." It was about the shameful waste of human potential that every war entails.
You can read the original proclamation here. It begins:
Arise, then, women of this day! Arise, all women who have hearts, whether your baptism be that of water or tears!
Say firmly: "We will not have great questions decided by irrelevant agencies. Our husbands shall not come to us, reeking with carnage, for caresses and applause. Our sons shall not be taken from us to unlearn all that we have taught them of charity, mercy and patience. We women of one country will be too tender of those of another to allow our sons to be trained to injure theirs."