Old Tools, New Problems

In some corners of Washington, D.C., there is a new push to dust off an 18th-century relic: letters of marque and reprisal. Once used to deputize private citizens for battle on the high seas, these instruments are now being floated by Congress as a means of cyber retaliation against digital aggression. The underlying rationale: if pirates once threatened commerce back then, cyber criminals do so now.

The allure of the past is powerful, especially when modern threats feel unruly, ungoverned, and unchecked. But romanticizing old strategies does not solve new problems. What was used to marshal wooden ships for naval skirmishes is mismatched to the speed, opacity, and legality of today’s cyber domain. The digital battlefield demands something different.

Modern threats require modern tools, and privatized cyber retaliation undermines U.S. national security, stability, and sovereignty—facts that merit serious attention.

What Are Letters of Marque and Reprisal?

Letters of marque and reprisal are two separate instruments,  most often used concurrently. A letter of marque grants passage beyond a country’s borders and a letter of reprisal grants the use of force (and the authority to seize) to redress a past harm. These enumerated powers represent two of our Constitution’s more radical grants of authority to private citizens. Rooted in medieval maritime practice, these laws authorized privately owned vessels to engage in acts of war or retaliation on behalf of the state. That authority is embedded in Article I, Section 8, Clause 11, and empowers Congress to “grant Letters of Marque and Reprisal”—a clause distinct from, and concomitant with, their power to declare war.

The Federalist Papers reinforced this intent: in Federalist No. 44, James Madison argued that vesting this power in Congress ensured that hostile actions abroad remained under national—not individual—control. The Articles of Confederation had granted similar authority (in Article VI) but restricted its use by individual states, underscoring the need for centralized discretion to avoid unintended conflict.

There is no doubt that Congress has broad authority in granting letters of marque or reprisal. Indeed, judicial interpretation has largely deferred to congressional discretion. As noted in Barron v. Baltimore, the clause imposes no restrictions beyond those implicit in broader war powers. Chief Justice Marshall’s interpretation indicated that such letters would carry the weight of a de facto act of war (“which is expressly given to congress.”), even today.

In practice, letters of marque and reprisal transformed a private actor (a shipowner) into a state-sanctioned privateer, authorized to seize enemy vessels and cargo for profit. This created a quasi-mercenary model of warfare, aligning personal economic gain with national strategic interest. The licensee bore the risk and reaped the reward, while the government maintained a distance from the operations and avoided the cost of maintaining a force. An old-school win-win scenario.

Today, some see a compelling analog for use of this authority in cyberspace. The idea of deputizing private actors—ethical hackers, red teams, or contractor collectives—engaging in cyber retaliation against foreign adversaries echoes the logic of letters of marque. Therefore, in a digital theater where attribution is murky and rules of engagement remain unsettled, some have proposed “cyber letters of marque” to allow private actors to strike back while the government maintains distance.

Yet this notion raises weighty questions. Would such authorization blur the line between public defense and private vendetta? Could it incentivize vigilantism under patriotic guise? Do letters of marque and reprisal apply in a digital world? How are other powers likely to respond to the U.S. bringing back this practice? The model demands scrutiny—not only of its efficacy, but of its oversight, escalation risks, and compliance with international law.

Why Were Letters of Marque and Reprisal Used?

In the early Republic, strategic ambition far outpaced operational capacity. The United States lacked a standing army, lacked a substantial naval power, and possessed neither the fiscal means nor institutional infrastructure to project force reliably. Letters of marque and reprisal offered a workaround—an asymmetric lever to outsource offense and expand capacity.

The United States was very familiar with the use of privateers developed by England in the late 16^th Century. The model was simple and scalable: incentivize citizens with economic gain to perform acts of coercion and disrupt an adversary’s economy. In an era when maritime mobility defined geopolitical power, a single galleon armed with state authorization became a cost-effective ally. The early United States similarly authorized private vessels to act as official war instruments from the American Revolution through the Civil War.

These letters were naval broadsides and economic scalpels. Privateers targeted the lifelines of enemy commerce, hijacking not just cargo but confidence. In wars of attrition and distance, they served as distributed tools of economic warfare: raiding merchant fleets, disrupting trade routes, and diverting naval resources to convoy protection.

This was also a strategy by subtraction. Every intercepted ship depleted enemy revenue, strained supply chains, and forced adversaries to reallocate assets to defense.

Some privateers even extracted ransom payments from seized ship captains, blurring the line between public war aims and private profiteering.

Given the multiple benefits letters of marque and reprisal conferred, Congress relied on them,  heavily in the American Revolution, transforming merchant ships into a maritime militia. These vessels disrupted British supply lines, diverted imperial forces, and turned transatlantic commerce into a contested battlespace.

By the War of 1812, privateering had matured into a national enterprise—American privateers captured over three times the number of British vessels seized by the U.S. Navy. Yet by mid-century, the United States had professionalized its military. The 1856 Declaration of Paris abolished privateering, and the subsequent Hague Conventions (including, 1899, 1907, 1949) cemented the state’s monopoly on legitimate force.

Though the practice of privateering disappeared among civilized nations, the idea lingers in the halls of Congress.

After the terrorist attacks on September 11, 2001, as the U.S. confronted diffuse terror networks, some in Congress revisited the concept of letters of marque and reprisal in a new light, wondering whether sanctioned private action might offer agility where conventional tools lagged. A similar conversation emerged during the 2007–2009 Somali piracy crisis, when commercial vessels were vulnerable and naval resources stretched thin. From 2011 to 2020, as cyber threats escalated, new debates surfaced over whether active defense—including limited offensive cyber operations—could convert from analog to digital privateering.Most recently, in 2025, Representative David Schweikert (R-Arizona) proposed granting these authorities to combat cybercrimes. This proposal reveals a long standing pattern: when conventional capacity appears insufficient, policymakers search for legal levers to harness private capability in defense of public ends.

Why the Cyber Privateer Tempts Today

The cyber domain resembles the 18th-century seas in one way: it’s vast and teeming with nonstate actors. Ransomware gangs, proxy hackers, and foreign intelligence fronts operate with relative impunity. Policymakers frustrated by slow federal response sometimes imagine a digital analog to privateering—authorizing ethical hackers or contractor collectives to retaliate.

The logic is seductive. The private sector owns and operates most U.S. digital infrastructure and employs much of the nation’s top technical talent. In a domain where deterrence depends on agility, strength, and credibility, why not enlist them to strike back?

The foundational risk of privatized cyber retaliation is that it fractures the state’s monopoly on force. Authorizing private retaliation blurs the distinctions between combatants and civilians because private actors don’t wear uniforms or operate under clear command structures, and exposes innocent parties to counterattack because adversaries may strike back at broader targets they can identify. And this undermines diplomatic efforts to promote responsible state behavior because it signals that the U.S. itself doesn’t follow the norms it promotes internationally.The perils of this idea are profound. Privateers historically operated under clear oversight in global commons taking prizes from identifiable foreign targets; in contrast, the Internet operates as a network of private computers, there are few prizes to seize, and cyber attribution is often probabilistic at best. A misfired counterstrike could hit the wrong system, harm civilians, or provoke international crisis. Malware doesn’t fly a flag of origin. Moreover, cyber effects are rarely contained. A “proportionate” digital counterattack could ripple across global networks, crippling hospitals, banks, or utilities far beyond its intended target. Delegating such power to private actors—even under congressional sanction—risks chaos.

Reviving it digitally would blur the line between national defense and vigilantism, inviting reciprocal behavior by adversaries.

Cyber retaliation is also not consequence-free. If a private actor, acting under U.S. sanction, misfires—targeting the wrong system, triggering collateral damage, or provoking diplomatic fallout—who bears the responsibility? Unlike legal analogues such as qui tam suits or citizen’s arrest, which operate under narrow constraints and judicial oversight, cyber privateering would authorize offensive actions against foreign targets. That exceeds both legal tradition and strategic prudence. At best, it introduces instability; at worst, it abdicates sovereign responsibility in favor of privatized retaliation.

Endorsing cyber privateering would undermine diplomatic efforts to promote responsible state behavior in cyberspace. Worse, it would set a dangerous precedent. If the U.S. deputizes private cyber actors, it implicitly greenlights other states—or their proxies—to do the same. The result would not be strategic parity, but normative unraveling. And tantamount to cyber war.

Modern Models for Modern Threats

While letters of marque served as an ad hoc solution for young nations contesting a more powerful global empire, any cyber equivalent today must evolve beyond that model to be structured, legal, and coordinated. The multinational operations against Emotet, Hive, and LockBit showcase the effectiveness of interagency and international collaboration. By combining intelligence, multinational law enforcement actions, and private-sector expertise, these operations dismantled criminal infrastructure without breaching legal or ethical lines.

Similarly, U.S. Cyber Command’s “defend forward” posture enables proactive disruption of foreign adversaries while maintaining state accountability. These coordinated, lawful responses achieve what cyber privateering promises—but safely and consistent with international law.

The private sector remains indispensable, but not as digital mercenaries. Microsoft’s Digital Crimes Unit, for example, uses litigation and partnerships to dismantle global botnets and cybercrime services; firms like Elliptic and Telegram trace illicit crypto flows to disrupt transnational crime. These operations leverage innovation and market influence without crossing into unauthorized offense.The legal framework must evolve in parallel. Indeed, Congress exercised an adjacent enumerated power (Article I, Section 8, clause 18) to pass the 2015 Cybersecurity Information Sharing Act, (CISA 2015) offering liability protections for private-sector threat reporting without endorsing offense. Expanding structured pathways for data sharing, clarifying defensive norms, and reinforcing legal protections would build on that precedent and strengthen collective security without inviting abuse or destabilizing the international order. As Congress revisits this law before it expires on January 30, 2026, it should assess the successes of actions under CISA 2015 and double-down on them, making room for more partnership, emerging technologies, and participants.

History’s Warning, Not Blueprint

Reviving letters of marque and reprisal in cyberspace would not make America safer. It would make cyberspace less stable, less predictable, and less governed. True deterrence today depends on disciplined public-private coordination, international cooperation, and lawful transparency—principles far more powerful than any 18th-century license to plunder.

The Founders gave us imagination and constitutional scaffolding, not timeless policy templates. They expected future generations to adapt. In that spirit, the next generation of cyber defense must be deliberate, lawful, and modern—an architecture worthy of the world it protects.

Devin Lynch is a Senior Director at the Paladin Global Institute and a Lecturer at the George Washington University’s Elliott School of International Affairs. He is a former Director for Cyber Policy & Strategy Implementation at the Office of the National Cyber Director, a veteran of the conflicts in Iraq and Afghanistan, and served two tours of duty on Capitol Hill. The views expressed are the author’s and do not reflect those of any government organization or entity, including but not limited to the Department of War and Department of Navy.