1. A method in a computer system for distributing rules of security policies to enforcement engines for enforcing the security policies, the method comprising: providing at the computer system enforcement engines that implement different layers of security enforcement; receiving and storing at the computer system security policies having rules, each rule having a rule type; under control of a firewall agent executing on the computer system, retrieving the stored security policies; and for rules of a retrieved security policy, identifying an enforcement engine to which a rule applies based on the rule type of the rule; and providing the rule to the identified enforcement engine; and under control of the enforcement engines, enforcing the rules provided to the enforcement engine by the firewall agent, wherein the firewall agent provides a mechanism for distributing the rules to multiple enforcement engines of the computer system.