"The Anarchists answer that the abolition of the State will leave in existence a defensive association, resting no longer on a compulsory but on a voluntary basis, which will restrain invaders by any means that may prove necessary"

This quote by Benjamin Tucker speaks to the idea of anarchism, which is the belief that the state should be eliminated and replaced with a voluntary association. This association would be accountable for defending against intruders, and would be able to utilize whatever indicates needed to do so. This is in contrast to the existing system, which depends on a mandatory system of defense, such as a standing army. Anarchists think that a voluntary association would be more efficient and effective in preventing intruders, as it would be based upon the consent of individuals. This quote speaks to the concept that the state is not necessary for defense, and that a voluntary association might be simply as effective.