Sunday's dramatic rescue of Capt. Richard Phillips brings to a felicitous end an incident involving the most egregious assault on U.S. commercial shipping in two centuries. The last time maritime marauders were so bold, Thomas Jefferson and James Madison tasked the fledgling U.S. Navy and Marine Corps with taking the fight to the pirate havens along the "shores of Tripoli." This weekend's incident highlights what the world's best-trained military can accomplish under the right conditions. But it also underscores the limits of force in the face of a seemingly intractable challenge posed by the Somali pirates.

According to the International Maritime Bureau, 111 of the 293 incidents of piracy or armed robbery at sea in 2008 took place off the coast of Somalia -- double the number from the preceding year. And 2009 is hardly off to an auspicious start. In spite of poor meteorological conditions -- hardly favorable for maritime forays -- there have already been more than a dozen seizures so far this year.

The pirates aren't just getting lucky. Indeed, Somali piracy is quite the opposite of the helter-skelter often portrayed in the media; it is a highly structured enterprise built around a number of syndicates. Pirate bases in Eyl, in the northeastern Puntland region, and in Xarardheere, in central Somalia, stand out for their audacity and for the resources they command. The syndicates operate "mother ships" far offshore that serve as long-range platforms for the speedboats that attack commercial vessels; they own depots along the coast where the pirates resupply before bringing captured boats to their main bases; and they coordinate the networks to support pirate operations on land. A report to the U.N. Security Council last month by Secretary-General Ban Ki-moon plaintively conceded that "these groups now rival established Somali authorities in terms of their military capabilities and resource bases."

Not only are the Somali pirates well-organized, but they have proven to be highly resilient to changes in the strategic environment. As I warned in an analysis two weeks ago, the pirates have not been intimidated by the international naval force that has assembled to prevent a repeat of last year's hijackings. Instead, they have shifted their operations to less patrolled areas, with strikes increasingly taking place farther and farther from the coast, on the high seas of the western Indian Ocean. The attempted seizure of the Maersk Alabama, for example, took place approximately 240 nautical miles southeast of the Somali shore. Mother ships, which resemble fishing vessels, have also worked hard to confuse antipirate patrols by avoiding the Somali coast altogether, docking instead at ports in other countries for refueling and resupplying (the U.N. report identified Al Mukalla and Al Shishr in Yemen).

Historically, piracy has been a crime of opportunity, and there are few places with conditions more favorable than the de facto statelessness that has afflicted Somalia since the collapse of the country's last effective government in 1991. In this Hobbesian state, all sorts of individuals have become stakeholders in the political economy of piracy. In exchange for a share in the eventual ransoms, wealthy Somali businessmen finance the purchase and outfit of mother ships and skiffs as well as the recruitment and arming of their crews. In various ports, paid informants send information about vessels' defenses, crews, cargos, and itineraries, enabling pirate gangs to select their targets and plot courses for interception. The Maersk Alabama, for example, had left Djibouti en route for Mombasa, Kenya, four days before it was hijacked; that information alone would have enabled a potential attacker to narrow the search for it, even without the automatic identification system (AIS) transmitting on board, radar, and other technologies.

Once a vessel is seized and brought to a pirate base, negotiations begin between the pirates and representatives of the ship's owner and its insurer. Eventually, the ransom, which is nowadays typically about $1 million -- although $3.2 million and $3 million, respectively, were paid to the captors of the Ukrainian-owned weapons freighter Faina and the Saudi-owned supertanker Sirius Star earlier this year -- must be delivered directly to the hijacked vessel by agreed-upon intermediaries, usually rather specialized security consultants.

Although many people are involved in the process -- from the dealers who supply the pirates with the fuel to sail out, to the prostitutes who entertain them on their return -- some are more susceptible than others to pressure from the international community. Certainly, pirate financiers in the Somali diaspora are targets for legal proceedings if evidence can be found of their role. Ship owners and insurers also bear a measure of responsibility because their ransom payments are incentivizing more and more Somalis to embark on careers in piracy.

Other profiteers to target include the regional Puntland government and al-Shabab, the al Qaeda-linked Islamist militant group that was formally designated a "foreign terrorist organization" last year by the U.S. State Department. Both entities receive a portion of the proceeds in exchange for allowing the pirates to operate in areas they control. That's an opportunity for a crackdown: A case could be made that the payment or handling of ransom is prohibited under international treaties (such as the U.N. Convention Against Corruption), U.S. domestic legislation (such as the Foreign Corrupt Practices Act), or other laws covering the finance and material support of terrorism.

Still, Somalis are going to have to step up. Because piracy plays a huge economic role in communities where the marauders are based, attacking the enterprise requires building up local political and security capabilities so as to reduce the extent of the areas of "lawlessness" that the pirates have exploited up to now. Such a strategy includes developing a coast guard, perhaps initially under African Union or subregional auspices, that would constantly patrol the region along the shore. Over time, this coast guard might acquire the wherewithal to collect and process information useful in taking down the pirate networks altogether. Even if it was never as sophisticated as that, a local coastal patrol has better prospects for sustainability than the continued massive presence of warships from the blue-water navies of the world.

Undoubtedly, a robust military response like that delivered Sunday by the U.S. Navy to the captors of Captain Phillips (and the French Navy last Friday to the pirates holding the yacht Tanit and its French civilian passengers) will be needed again to deal with pirate actions underway and to deter other potential maritime hijackings. Of course, as Bjoern Seibert convincingly argued here two weeks ago, the various naval efforts need to be better coordinated, if not integrated. Ultimately, however, piracy is far more complex than any naval patrol; it will require more than just the application of force to uproot piracy from the soil of Somalia.