Its not just a breach of contract, because Aaron accessed the network again after his license had been revoked. That was a distinct violation in the nature of trespass, a property law concept.
Let me illustrate. Say you belong to a private club. The contract of membership allows you to use the clubhouse, as long as you don't bring any Hindu guests. Say one day you do. That's a breach of contract. Say you come back the next day. Since you've breached the contract, your license to use the house is revoked, and now its an infringement of property: trespass. Finally, lets say you punch the owner for being racist. Any classic libertarian will support prosecuting you under three legal theories: breach of contract, trespass, and battery (a tort). Classic libertarians don't reject any of these.
Let me illustrate. Say you belong to a private club. The contract of membership allows you to use the clubhouse, as long as you don't bring any Hindu guests. Say one day you do. That's a breach of contract. Say you come back the next day. Since you've breached the contract, your license to use the house is revoked, and now its an infringement of property: trespass. Finally, lets say you punch the owner for being racist. Any classic libertarian will support prosecuting you under three legal theories: breach of contract, trespass, and battery (a tort). Classic libertarians don't reject any of these.