Part I: The Conceptual and Lexical Landscape of “Enemy”

Section 1.1: Etymology and Foundational Definitions

The term “enemy” is a powerful and emotionally charged word, whose meaning extends far beyond a simple dictionary definition. Its origins trace back to the Latin word inimicus, a compound of the prefix in- (“not”) and amicus (“friend”).¹ This etymological root—”un-friend”—is deeply significant, suggesting that the concept of an enemy is, at its core, a betrayal of a bond or a relationship that could or should have been one of friendship.³ This emotional foundation is reflected in the strong feelings the word can evoke, including anger, hatred, frustration, fear, and distrust.³

At its most basic level, an enemy is defined as an individual or group that is forcefully adverse or threatening.⁴ It is a concept that is considered fundamental for both individuals and communities, as it serves the crucial social function of designating a particular entity as a threat.⁴ This designation is not merely descriptive; it is intended to invoke an intense emotional and often aggressive response.⁴ The definition extends beyond a personal adversary to encompass broader concepts. For example, a military adversary is an enemy ¹, but so too can be an abstract idea like “progress” or a harmful substance like “alcohol”.¹ This linguistic flexibility underscores the term’s function as a potent metaphor for any force perceived as a threat or hindrance to a goal. This fundamental tension between the word’s broad, subjective, and emotionally charged linguistic use and the need for legal precision is a central theme in U.S. law, particularly concerning treason.

Section 1.2: Broader Applications and Sociopolitical Function

In a broader societal context, the term “enemy” often functions as a tool for political and social manipulation. The act of characterizing a person or group as an enemy is known as “demonization,” a process that is a major component of propaganda.⁴ Throughout history, the designation of “the enemy” has been a prototypical propaganda tool used to focus the fear and anxiety of a society toward a particular target.⁴ This target can be a specific military force, an ethnic group, or even an abstract ideology.⁴ A government may also use the term “public enemy” to represent a person or group as a threat to the public good, while the concept of the “enemy within” is used to describe a domestic threat.¹ The use of such terms, as seen during the Cold War when “Communists” or “Reds” became synonymous with “the enemy,” demonstrates how the popular definition of an adversary is often deliberately imprecise and subjective, designed to stir public emotion and justify actions that might otherwise be unconscionable.⁴

This tendency for the term to be used as a political construct stands in stark contrast to the legal requirements of a precise and objective definition. The Framers of the U.S. Constitution were acutely aware of this distinction, having witnessed how the English Crown used vague treason laws to suppress political opposition.⁶ Their decision to craft a narrow, constitutionally-defined crime of treason was a direct response to the dangers posed by a broad, politically-motivated application of the word “enemy.” This shows a foundational American principle: the government must be prevented from using emotionally charged language to criminalize thought, speech, or mere dissent.

Part II: The Constitutional Framework of Treason

Section 2.1: The Text of Article III, Section 3

The United States Constitution provides the sole and exhaustive legal definition of treason. Article III, Section 3, Clause 1 states, “Treason against the United States, shall consist only in levying War against them, or in adhering to their Enemies, giving them Aid and Comfort”.⁶ This language is a deliberate and restrictive measure, limiting the crime to only two distinct acts. The Constitution explicitly places this power beyond the reach of Congress to expand or alter.⁶

The Constitution goes a step further by establishing a stringent procedural barrier for conviction, a direct counterpoint to the broad nature of the linguistic term. It requires that “No Person shall be convicted of Treason unless on the Testimony of two Witnesses to the same overt Act, or on Confession in open Court”.⁶ This “two-witness rule” is a formidable evidentiary hurdle, making it exceptionally difficult to secure a conviction.¹¹ The presence of both a substantive and procedural limitation on a federal crime is unique to treason, highlighting the extraordinary caution with which the Framers approached this offense.¹¹

Section 2.2: The Framers’ Intent and the English Precedent

The narrow constitutional definition of treason is not an accident of legal design but a core principle of American civil liberties. This was a direct reaction to the Framers’ experience with the English law of treason, which had been used by the English Crown to suppress political dissent.⁶ The English Statute of Treason (1350) had a clause that criminalized “compassing or imagin[ing] the death of our lord the King,” which the English monarchy leveraged to prosecute political opponents on capital charges for little more than speech or ideas.⁷ The Framers sought to prevent such abuse by creating a “restrictive concept of the crime of treason”.⁶

By defining treason in the Constitution itself, they deliberately restricted Congress’s power to change the definition or make it easier to prove.⁶ This act served as a proactive measure to prevent the ruling class from using the crime of treason to “eliminate their political dissidents”.⁶ The inclusion of the “two-witness” rule was another layer of protection, designed to make it challenging to establish that someone had committed the crime and to ensure that convictions would not be based on vague or circumstantial evidence.⁶ The Framers’ decision demonstrates a deep-seated suspicion of government power and a commitment to protecting individual freedom of expression, even in the context of the most serious crime against the state.

Section 2.3: The Legal Elements of the Crime

The crime of treason, under the “adhering to their Enemies” clause, consists of two core legal elements: 1) a person’s “adherence or loyalty to an enemy of the United States,” and 2) the act of “providing aid or comfort to the enemy”.⁶ An essential component of this crime is the “specific intent to betray” the United States.¹⁰ As Justice Robert Jackson articulated in

Cramer v. United States (1945), a person can take actions that may aid an enemy, but “if there is no adherence to the enemy in this, if there is no intent to betray, there is no treason”.⁶ This is a critical distinction, as it protects a citizen who might, for example, criticize the government during wartime or organize a strike in a defense plant without the intent to assist an enemy’s plan or design.⁶

The second element, the “overt act,” is equally crucial. It is the physical manifestation of treasonous intent, an action that has moved from “the realm of thought into the realm of action”.⁶ The Constitution mandates that this act must be supported by the testimony of two witnesses.⁶ The Supreme Court has specified that the overt act must be of a nature that an inference of treasonous intent can be drawn from the act and its surrounding circumstances.¹¹ It must be an intentional deed or physical activity, not merely a “mental operation”.⁶ This high bar for evidence and the requirement of specific intent have made treason, by design, the most difficult federal crime to prove.¹¹

Part III: The Judicial Interpretation of “Enemies of the United States”

Section 3.1: The Requirement of Armed Hostilities

The first significant judicial interpretations of the Treason Clause emerged from the early 19th-century trials of Aaron Burr and his associates.¹¹ In

Ex parte Bollman (1807), Chief Justice John Marshall established a pivotal precedent regarding the “levying War” prong of treason.¹⁴ Marshall ruled that the crime required the “actual waging of war” and the “assemblage of men for a purpose treasonable in itself”.¹⁴ He distinguished this from a mere conspiracy to levy war, which he held was insufficient for a treason conviction.¹⁴ This foundational ruling implicitly tied the concept of a constitutional “enemy” to an organized, state-like body of people engaged in an armed conflict with the United States.¹¹

This judicial focus on an “actual assemblage of men” and “armed hostilities” implies that a constitutional enemy is not just any hostile individual or group, but a formally organized entity, likely a sovereign nation or a belligerent force engaged in a war.¹⁴ This is a significant constraint that distinguishes a legal enemy from the many types of adversaries a nation might face. The legal term “enemy” is fundamentally tethered to the existence of an armed conflict or belligerent status between nation-states, a concept that struggles to accommodate modern, decentralized, non-state threats.

Section 3.2: Clarifying the Overt Act in Modern Treason Cases

The modern interpretation of the “adhering to their Enemies” clause was largely forged during a series of World War II cases. The first of these was Cramer v. United States (1945), which involved a naturalized U.S. citizen, Anthony Cramer, who was accused of treason for his associations with German saboteurs who had entered the country.¹⁶ The Supreme Court, in a 5-4 decision, overturned his conviction.¹³ Justice Jackson, writing for the majority, held that the government failed to prove an overt act of giving “aid and comfort” to the enemy.¹³ He argued that the overt act must, on its face, provide some form of assistance and be independently witnessed by two people.¹³ His ruling reinforced the high evidentiary standard set by the Constitution, noting that the acts alleged were insufficient to justify an inference of treasonous intent.¹¹

Just two years later, in Haupt v. United States (1947), the Supreme Court upheld a treason conviction for the first time in its history.¹¹ In this case, the defendant, Hans Haupt, was convicted for harboring his son, a German spy, and assisting him in purchasing an automobile and obtaining employment in a defense plant.¹³ The Court found that while these acts might seem “natural” for a father, the prosecution’s proof that Haupt knew of his son’s treasonous mission established the necessary “specific intent to betray”.¹³ This case clarified that while an act may be ambiguous on its face, the inference of treasonous intent can be drawn from the act in conjunction with the surrounding circumstances.¹¹ Finally, in

Kawakita v. United States (1952), the Court established that a U.S. citizen could be charged with treason for acts committed anywhere in the world, as allegiance to the United States has no geographical boundaries.¹¹

To provide a clear overview of the evolution of the legal interpretation of the Treason Clause, the following table summarizes the key Supreme Court cases discussed above.

Table 1: Key Supreme Court Treason Cases

Case Name	Year	Primary Legal Question	Court’s Holding	Significance/Precedent Set
Ex parte Bollman	1807	What constitutes “levying War”?	Ruled that conspiracy to levy war is not treason; requires an “actual assemblage of men”.14	Established a strict, narrow interpretation of the “levying War” clause, tying treason to organized, military-like conflict.11
Ex parte Milligan	1866	Can civilians be tried by military tribunals?	Ruled that military tribunals cannot try civilians where civil courts are operating.19	Affirmed that civilian legal processes and protections, including those for treason, cannot be suspended during wartime if civilian courts are functional.19
Cramer v. United States	1945	What constitutes a treasonous “overt act”?	Overturned conviction; held that the overt act itself must manifest treasonous intent and be supported by two witnesses.13	Reinforced the high evidentiary bar and the protective intent of the Treason Clause, requiring demonstrable intent from the overt act.13
Haupt v. United States	1947	Can seemingly innocent acts be treasonous?	Upheld conviction; ruled that an act’s treasonous nature can be inferred from the act and surrounding circumstances, provided specific intent is proven.11	Clarified that ambiguous acts can constitute treason if they are part of a broader, provably treasonous design with specific intent to betray.11
Kawakita v. United States	1952	Does treason have geographical boundaries?	Upheld conviction of a dual citizen; ruled that U.S. citizens can be charged with treason for acts committed anywhere in the world.11	Established that a U.S. citizen’s allegiance and liability for treason are not limited by geography.11

Section 3.3: The Modern Legal Status of Non-State Actors as “Enemies”

The traditional legal definition of an “enemy” as a sovereign power or a body of people engaged in state-like armed conflict presents a significant challenge in the modern era.²¹ This is particularly true in the context of the “War on Terror,” which is fought against decentralized, non-state groups like al-Qaeda and ISIS. Since these groups do not fit the traditional model of a state-based military adversary, the U.S. government has largely avoided using treason charges against them.¹²

Instead, the government created and used the term “enemy combatant” to describe individuals involved in or supporting terrorist activities.²² This legal designation, introduced by the George W. Bush administration after the September 11, 2001, attacks, was a strategic move to allow the indefinite detention of individuals without formal charges or the standard protections of the U.S. criminal justice system or the Geneva Conventions.²² This new classification, which the Obama administration later discontinued using but maintained the practice of detention, was specifically designed to bypass the constitutional difficulties inherent in a treason prosecution.²² While some legal scholars have argued that terrorist groups can be considered “enemies” under the Treason Clause if they pose a “state-like threat,” the government has found it more pragmatic to rely on other legal tools that do not carry the high evidentiary burden of treason.²⁴ The government’s preference for using the “enemy combatant” designation and other terrorism-related statutes demonstrates a strategic choice to prioritize prosecutorial efficiency over the constitutional safeguards embedded in the Treason Clause.

Part IV: Treason in the Modern Era: Disuse and Alternatives

Section 4.1: The Rarity of Treason Prosecutions

Treason charges in the United States are exceptionally rare. Since the Constitution’s adoption, there have been fewer than 40 federal prosecutions for treason, and only 13 have resulted in a conviction.¹⁰ Only three people have been executed for treason under the Constitution.¹⁰ The last significant Supreme Court cases on treason were decided in the mid-20th century, and there have been no additional rulings since.¹¹ Despite its disuse, a treason accusation still carries immense symbolic weight, as it is framed by the government as a crime “against America itself”.¹²

Section 4.2: The Rise of Alternative Federal Crimes

The rarity of treason charges is not an indication of a lack of betrayal but rather a deliberate legal strategy. Over the past century, Congress has passed numerous laws that address subversive activities without having to meet the difficult constitutional standards for treason.¹⁰ These statutes are more specific in their definitions, making them easier to prosecute.¹⁰ Key alternatives include:

• Sedition (18 U.S.C. § 2384): Defined as a conspiracy to “overthrow, put down, or to destroy by force” the U.S. government.¹⁰ Sedition is considered a lesser crime than treason and focuses on encouraging rebellion, not necessarily providing aid to a foreign enemy.²⁷
• Espionage (18 U.S.C. § 792 – 798): The act of obtaining, transmitting, or delivering national defense information to an unauthorized person, often a foreign government.¹⁰ While it can involve giving assistance to another country, it is a separate crime from treason and is not subject to the Treason Clause’s two-witness rule.¹⁸
• Material Support for Terrorism (18 U.S.C. § 2339B): These charges have become a primary tool for prosecuting terrorism-related offenses. They are a favored legal alternative because they do not require proof of allegiance to the United States, allowing both citizens and non-citizens to be charged.³⁰ These charges also have a lower burden of proof, criminalizing conduct far removed from an actual plot and dispensing with the strict evidentiary restrictions of the Treason Clause.¹²

The following table provides a clear comparison of the legal frameworks for treason and these alternative federal crimes.

Table 2: Treason vs. Alternative Federal Crimes

Crime	Legal Basis	Key Elements of Culpability	Evidentiary Requirements	Historical or Modern Application
Treason	U.S. Constitution, Article III, Section 3 8	Specific intent to betray, coupled with either levying war or giving aid and comfort to a constitutional enemy.6	Two witnesses to the same overt act or a confession in open court.6	Historically used in wartime, but rarely charged since the mid-20th century.10
Sedition	Federal Statute (18 U.S.C. § 2384) 10	Conspiring to overthrow or put down the government by force.10	Standard criminal evidentiary rules apply, not the two-witness rule.10	Rarely charged, but used in cases like the prosecution of those involved in the January 6 Capitol riot.10
Espionage	Federal Statute (18 U.S.C. § 792) 10	Obtaining or transmitting national defense information to an unauthorized person with harmful intent.10	Standard criminal evidentiary rules apply, not the two-witness rule.18	A common modern charge for acts of spying or leaking classified information.28
Material Support for Terrorism	Federal Statute (18 U.S.C. § 2339A)	Providing resources (e.g., money, lodging, weapons, training) to a designated terrorist organization.12	Standard criminal evidentiary rules apply, lower bar for proving intent.12	The most common modern charge for acts related to terrorism; allows prosecution of citizens and non-citizens.30

Section 4.3: Legal and Sociocultural Explanations for the Shift

The virtual disappearance of treason charges in the modern era can be attributed to both legal and sociocultural factors. From a legal perspective, the high burden of proof is the most significant deterrent for prosecutors. The constitutional requirements of a specific intent to betray, coupled with the stringent “two-witness” rule, are exceptionally difficult to satisfy in court.¹¹ In contrast, the alternative statutes passed by Congress are more flexible and have a lower bar for proving guilt.¹² Charges for material support for terrorism, for example, criminalize a broader range of conduct and require a lesser showing of intent, making them a more efficient and powerful tool for the government.¹²

From a sociocultural standpoint, a treason accusation “presupposes shared belonging in a political community”.¹² The charge is most effective when the government and the public view the accused as a fellow citizen who has betrayed a common national identity. However, in the context of the “War on Terror,” many defendants, even if they are U.S. citizens, are perceived as “racial and religious outsiders” by a segment of the American population.¹² This perception makes a treason charge—a crime of betrayal from within—feel less fitting than charges of “international” terrorism or the designation of an “enemy combatant,” which frame the conflict as external.¹² This allows the government to cast the conflict as a foreign threat, even when it involves its own citizens.

Conclusion

This report has deconstructed the complex and multifaceted meaning of “enemy,” revealing a profound divergence between its general linguistic use and its specific legal definition under U.S. law. In common lexicon, “enemy” is a broad, subjective, and emotionally charged term, often used as a tool for political and social demonization to focus fear and justify action.⁴ By contrast, the legal definition of “Enemies” in the context of U.S. treason law is a highly constrained, judicially-interpreted term.

The Framers of the Constitution, having witnessed the abuses of English treason law, intentionally crafted a narrow and procedurally difficult definition for the crime.⁶ Their decision to limit treason to acts of “levying War” or “adhering to their Enemies” was a deliberate effort to prevent the government from using the charge to suppress political dissent.⁷ Seminal Supreme Court cases, from

Ex parte Bollman to Cramer v. United States and Haupt v. United States, reinforced this narrow interpretation, cementing the legal requirements of armed hostilities, specific intent to betray, and a two-witness-supported overt act.¹³

This historical and judicial analysis culminates in the modern paradox: while the constitutional safeguard of the Treason Clause remains in place, its intentional difficulty has led the U.S. government to pursue alternative legal frameworks for prosecuting those who threaten national security.¹⁰ The proliferation of statutes addressing sedition, espionage, and, most notably, material support for terrorism, allows the government to achieve the same objectives as a treason charge—including imposing stigma and severe penalties—but without the constitutional constraints.¹² The result is a legal landscape where treason is a historically significant but rarely used charge, its purpose now largely supplanted by more flexible and easily prosecutable statutory crimes. This demonstrates that when a constitutional principle becomes a barrier to government action, the government will often seek to bypass it through legislative alternatives.

Works cited

1. ENEMY Definition & Meaning – Merriam-Webster, accessed August 31, 2025, https://www.merriam-webster.com/dictionary/enemy
2. Enemy – Etymology, Origin & Meaning, accessed August 31, 2025, https://www.etymonline.com/word/enemy
3. en.wikipedia.org, accessed August 31, 2025, https://en.wikipedia.org/wiki/Enemy#:~:text=Enemy%20comes%20from%20the%209th,%2C%20and%20possibly%20grudging%20respect%22.
4. Enemy – Wikipedia, accessed August 31, 2025, https://en.wikipedia.org/wiki/Enemy
5. Enemy Definition & Meaning | Britannica Dictionary, accessed August 31, 2025, https://www.britannica.com/dictionary/enemy
6. Treason Under the Constitution – FindLaw, accessed August 31, 2025, https://constitution.findlaw.com/article3/annotation24.html
7. Treason – US Constitution Annotated – Justia Law, accessed August 31, 2025, https://law.justia.com/constitution/us/article-3/42-treason.html
8. Article III Section 3 | Constitution Annotated | Congress.gov | Library of Congress, accessed August 31, 2025, https://constitution.congress.gov/browse/article-3/section-3/
9. Interpretation: Treason Clause – The National Constitution Center, accessed August 31, 2025, https://constitutioncenter.org/the-constitution/interpretations/does-the-treason-clause-still-matter
10. Federal Crime of Treason | 18 U.S. Code § 2381, accessed August 31, 2025, https://www.thefederalcriminalattorneys.com/federal-treason
11. Treason and the Supreme Court | EBSCO Research Starters, accessed August 31, 2025, https://www.ebsco.com/research-starters/law/treason-and-supreme-court
12. Terrorism, Not Treason: The Rise and Fall of Criminal Charges, accessed August 31, 2025, https://legal-forum.uchicago.edu/print-archive/terrorism-not-treason-rise-and-fall-criminal-charges
13. Aid and Comfort to the Enemy as Treason | U.S. Constitution …, accessed August 31, 2025, https://www.law.cornell.edu/constitution-conan/article-3/section-3/clause-1/aid-and-comfort-to-the-enemy-as-treason
14. ArtIII.S3.C1.2 Levying War as Treason – Constitution Annotated – Congress.gov, accessed August 31, 2025, https://constitution.congress.gov/browse/essay/artIII-S3-C1-2/ALDE_00013525/
15. Webster’s Dictionary 1828 – Enemy, accessed August 31, 2025, https://webstersdictionary1828.com/Dictionary/enemy
16. CRAMER v. UNITED STATES. | Supreme Court | US Law – Legal Information Institute, accessed August 31, 2025, https://www.law.cornell.edu/supremecourt/text/325/1
17. Cramer v. United States – Wikipedia, accessed August 31, 2025, https://en.wikipedia.org/wiki/Cramer_v._United_States
18. ArtIII.S3.C1.4 Aid and Comfort to the Enemy as Treason – Constitution Annotated, accessed August 31, 2025, https://constitution.congress.gov/browse/essay/artIII-S3-C1-4/ALDE_00013527/
19. Ex parte Milligan – Wikipedia, accessed August 31, 2025, https://en.wikipedia.org/wiki/Ex_parte_Milligan
20. Lambdin P. Milligan (Ex Parte Milligan) – Huntington County Honors, accessed August 31, 2025, https://www.huntingtoncountyhonors.org/Honorees/lambdin-p.-milligan-(ex-parte-milligan)
21. Enemy combatant – Wikipedia, accessed August 31, 2025, https://en.wikipedia.org/wiki/Enemy_combatant
22. enemy combatant | Wex | US Law | LII / Legal Information Institute, accessed August 31, 2025, https://www.law.cornell.edu/wex/enemy_combatant
23. Enemy Combatants: Overview | EBSCO Research Starters, accessed August 31, 2025, https://www.ebsco.com/research-starters/law/enemy-combatants-overview
24. Treason in the Age of Terrorism: An Explanation and Evaluation of Treason’s Return in Democratic States – Scholarship@Vanderbilt Law, accessed August 31, 2025, https://scholarship.law.vanderbilt.edu/cgi/viewcontent.cgi?article=1402&context=vjtl
25. Treason laws in the United States – Wikipedia, accessed August 31, 2025, https://en.wikipedia.org/wiki/Treason_laws_in_the_United_States
26. Sedition – Legal Dictionary | Law.com, accessed August 31, 2025, https://dictionary.law.com/Default.aspx?selected=1903
27. Sedition | EBSCO Research Starters, accessed August 31, 2025, https://www.ebsco.com/research-starters/law/sedition
28. Justice Manual | 2057. Synopses Of Key National Defense And National Security Provisions, accessed August 31, 2025, https://www.justice.gov/archives/jm/criminal-resource-manual-2057-synopses-key-national-defense-and-national-security-provisions
29. Difference between espionage and treason – Legal English – Anglofon Studio, accessed August 31, 2025, https://egyetemi.anglofon.hu/blog/difference-between-espionage-and-treason
30. constitutioncenter.org, accessed August 31, 2025, https://constitutioncenter.org/the-constitution/interpretations/does-the-treason-clause-still-matter#:~:text=Unlike%20treason%2C%20the%20crime%20of,be%20charged%20with%20the%20offense.
31. Terrorism, Not Treason: The Rise and Fall of Criminal Charges – Chicago Unbound, accessed August 31, 2025, https://chicagounbound.uchicago.edu/uclf/vol2024/iss1/8/