Editor’s note: This blog post contains descriptions of rape and sexual assault. Reader’s discretion is advised.
I lived in Erlangen, Germany for much of 2009, getting around on a bicycle. After the big April beer festival, the “Bergkirchweih,” my lock was cut and my bike was thrown down a hill and set on fire (it may have been set on fire first, it was hard to tell).  So I called the police.
The two policemen (one spoke English, fortunately) spent about 30 seconds total “investigating.” They showed up, I told them what happened, and the English-speaking cop said, “You need a better lock.”  That was it; back in the car and off to more pressing business.
The job of the police is not really to protect the security of citizens, but to provide security for their employer, the State.  It’s true that the interests of citizens and the State often coincide—property must be protected for the state to collect taxes—but they are not identical.  Consider the important, but not always understood, case of Warren vs. District of Columbia (1981; 444 A.2d. 1, D.C. Court of Appeals):
Three women, W, T, and D, shared a three-story house.  Two men smashed the back door and entered the house.  They began to rape and sexually abuse D, who slept on the second floor.  W and T, who shared the third floor, heard D screaming and begging the attackers to stop, and W called the police.
Although the dispatcher had been told that the burglars were in the house and that there was active danger, the police who showed up did no more than get out of their car, walk up to the front door, and knock.  When there was no answer, they left.  Desperate, W called the police again, frantically saying that her roommate was being raped.  The dispatcher simply ignored the request.
Believing that the police must be in the house by this time, and terrified by D’s screaming, W and T called down to her.  But since the police had slow-played the first call and ignored the second, the only people who heard the women were the rapists.  The men then abused all three women for the next 18 hours, alternating between rape and torture.
Now, I suppose you can’t really blame the police. Their job is to protect the State, so their line of thinking was no doubt something like what the German cops told me: “You ladies need a better back door.”  But the women, outraged at the clear failure to follow up, especially on the second call which was simply ignored, sued.  They were trying to get compensation for their medical bills and for the terrible pain and suffering that had been inflicted upon them as a consequence of what they saw as police negligence.
The complaint was dismissed, and the women appealed to the D.C. Circuit.  The judges of the D.C. Circuit ruled 4-3 that the lower court was correct in dismissing the suit.  The opinion is quite clear about the reasons for the dismissal:

A publicly maintained police force constitutes a basic governmental service provided to benefit the community at large by promoting public peace, safety and good order. The extent and quality of police protection afforded to the community necessarily depends upon the availability of public resources and upon legislative or administrative determinations concerning allocation of those resources. The public, through its representative officials, recruits, trains, maintains and disciplines its police force and determines the manner in which personnel are deployed. At any given time, publicly furnished police protection may accrue to the personal benefit of individual citizens, but at all times the needs and interests of the community at large predominate. Private resources and needs have little direct effect upon the nature of police services provided to the public. Accordingly, courts have without exception concluded that when a municipality or other governmental entity undertakes to furnish police services, it assumes a duty only to the public at large and not to individual members of the community. (DC Superior Court Memorandum Opinion, Appendix, emphasis added)“]
The reasoning is breathtaking, at least for those of you who think that the State is supposed to take care of its citizens. The opinion claims that the D.C. police could not, under any circumstances, have been negligent.  The facts of the case literally don’t matter.  Instead, what happened was that “the public, through its representative officials” was at fault for not providing the police with enough resources to protect citizens.  So whose fault was it?  Apparently those three women should have paid for private security since the State was apparently not capable, and was certainly not legally obliged, to help them.
Of course, if the State can ignore the protection of individuals, the duty to take care of “the community at large” is just legalistic code for “the State protects the State.” To put it more clearly: if no individual is entitled to protection by the State, then all security is private.
That doctrine might be acceptable if the State would allow individuals to protect themselves. And that is why “private security firms” are a centerpiece of many libertarian proposals for a better society.  Are there precedents?  After all, that’s the question we always get asked, right?  “Are there any examples where this crazy idea would actually work?”
The answer is yes:  security can be private.  One of the most interesting examples is the Holmes service, which combined on-site security (an alarm would sound if the electronic connections on doors and windows were broken) with a remote call for help (a telegraph signal of the security breach was sent to the Holmes central office). Rather than calling police (which didn’t work out very well for W, T, or D!), the Holmes device called private security guards, who are legally armed and fully uniformed.
Holmes, because it was a private contractor, could be fired, and if Holmes was negligent or incompetent, the company could be sued for damages. This provided Holmes with an incentive to perform security duties with care and trust and to improve its service by incorporating new technologies (which at the time included electro-magnetic connections, and the telegraph). With State security, you have to pay taxes whether you benefit from it or not, and you can’t “fire” the State security forces. This leaves State security unaccountable for any mistakes, negligence, or incompetence.
Now, one might prefer that the State actually had (1) the incentive and (2) the capacity to take care of citizens’ security needs.  But security is private and individual, and the State owes a duty only to (and has incentives to care about) “the public at large.”  The new internet of things brings opportunities for an analogous improvement in private security services.  This will require the consent of the State, in the form of a favorable (non-) regulatory regime, and the recognition of citizens that “you need a better lock” is actually a viable approach to protecting ourselves.