Anarchism as Justice?

Declan’s blog says:

“It is not enough for Mr. Kropotkin to simply assume his belief system is right and that “any man with a heart” would naturally resign himself to death upon committing whatever an anarchist subjectively declares is unholy. Any common criminal can convince himself of the worthiness of his punitive actions; however, without a common consensus of the injustice of the original action, punishment for such an action is limited to simple terrorism.”

What interests me about this post is the meditation on the role of justice and what it is. For Declan, justice is a communal enterprise: “Justice, of course, requires due process and a consensus among a body of people.” But what is justice? As I read this, he appears to be saying that justice is an historically emerging process, requiring a broad consent of those who obey these laws. After all, anarchists are a “body of people” if narrowly defined as such, and, given his dislike of anarchist rationalizations of violence, one possible way to distinguish them from an actually just grouping, is the assent of a broad grouping—say a majority? The corollary of Declan’s excellent observation is that—at what point can a minority actually resist an unjust distribution? I am thinking of any number of situations, both historical (civil rights) and in “literature” such as Rand’s Atlas Shrugged? Couldn’t a majority—or a broad consensus, argue that any aggravation on the part of the minority that broke the laws (civil disobedience?) be a form of terrorism, no matter how mild?