Are Human Shields a Problem for Libertarians?

     A common problem libertarians are faced with is the application of  the non-aggression principle in the case of human shields. Walter Block  attempted to come up with a solution through his “negative homesteading” theory,  with which I respectfully disagree. The problem is this: if A is  aggressing against C while using B to shield himself from all defensive  force from C, can C use force against B to stop A, and can B use force  against C in order to stop C from using force against him? I posit that  the libertarian approach is this: It is legitimate for C to use force  against aggressor A, and if A aggresses against B to put B in a position  to receive the force against him from C, than the one responsible for  the harm done to B is A, that the one initiating force against B is A,  not C, and that therefore B cannot legitimately use force against C  because that would be aggression, as C is not initiating force against  B, but simply having his defensive force blocked by A with an innocent  person. As an example situation, imagine that someone attacks you by  punching you, and you punch back, but as you are throwing your punch, he  grabs a person next to him and places that person in front of him,  causing this innocent person to receive the blow. Obviously (because  your force was directed at the aggressor) you did not aggress against  the innocent person, and, therefore should not be stopped from punching  by the innocent, as that would be an initiation of force against you.  The analysis is the same in a hostage situation in which the hostage is  taken not at the last moment but well before, and one in which fatal  force is used instead of a punch.

     “Collateral damage” is still aggression because it is not a case of  an aggressor using an innocent or innocents as a shield against  defensive force, but aggression by a person in the course of using or  attempting to use defensive force against an aggressor. For example, a  store owner who has been robbed would be an aggressor, in fact a worse  aggressor than the robber, if the robber ran into a crowd of people and  the store owner sprayed machine gun fire into the crowd. This theory is not a justification for aggression against third parties when using force against an aggressor.

     In conclusion, I hope this answer to a common objection will help  people put an end to one of their doubts regarding libertarianism