Former National Security Adviser Michael Flynn spokpe at a White House earlier this month. (Carolyn Kaster/AP)

Carlton F.W. Larson is a professor of law at the University of California at Davis and is writing a book about treason and the American Revolution.

President Trump promised to do things differently, but the resignation of a national security adviser under a cloud of suspicion of treason was novel even by Trump standards. The political (and social media) landscape is now littered with accusations of treason, not just against Trump officials but against all kinds of other actors as well — Hillary Clinton , Mitch McConnell , even the state of California . Treason is an ancient concept shrouded in misconceptions. Here are a few of the most common.

Myth No. 1

Disloyalty or policies that harm the United States are treason.

Accusations of treason have recently been made on the flimsiest of grounds, from assertions that President Barack Obama committed treason by supporting the Iran nuclear deal (found in James McCormack's book "Unexpected Treason") to claims that, per Paste magazine, Sen. John McCain committed treason because he threatened not to confirm a Supreme Court justice hypothetically nominated by Hillary Clinton.

The framers of the Constitution took deliberate steps to ensure that treason trials would not be used as political weapons against opponents. Article 3, Section 3 defines the crime very narrowly: "Treason against the United States shall consist only in levying war against them, or in adhering to their enemies, giving them aid and comfort." This language is drawn from an English statute from 1351 that was also intended to limit the scope of treason. Speaking against the government, undermining political opponents, supporting harmful policies or even placing the interests of another nation ahead of those of the United States are not acts of treason under the Constitution.

Myth No. 2

Aiding Russia is treason against the United States.

Stephen Colbert's recent segment "Michael Flynn's White House Tenure: It's Funny 'Cause It's Treason" was but one of many accusations of treason hurled against Flynn and other White House associates because of their proven or alleged ties to Russia. "Consider the evidence that Trump is a traitor," exhorted an essay in Salon. It is, in fact, treasonable to aid the "enemies" of the United States.

But enemies are defined very precisely under American treason law. An enemy is a nation or an organization with which the United States is in a declared or open war . Nations with whom we are formally at peace, such as Russia, are not enemies. (Indeed, a treason prosecution naming Russia as an enemy would be tantamount to a declaration of war.) Russia is a strategic adversary whose interests are frequently at odds with those of the United States, but for purposes of treason law it is no different than Canada or France or even the American Red Cross. The details of the alleged connections between Russia and Trump officials are therefore irrelevant to treason law.

This was true even in the 1950s, at the height of the Cold War. When Julius and Ethel Rosenberg handed over nuclear secrets to the Soviet Union, they were tried and executed for espionage, not treason. Indeed, Trump could give the U.S. nuclear codes to Vladimir Putin or bug the Oval Office with a direct line to the Kremlin and it would not be treason, as a legal matter. Of course, such conduct would violate various laws and would constitute grounds for impeachment as a “high crime and misdemeanor” — the framers fully understood that there could be cases of reprehensible disloyalty that might escape the narrow confines of the treason clause.

So who are the current enemies of the United States? North Korea is a possible enemy, since the Korean War was never formally concluded. Certain nonstate actors can also count as enemies, and terrorist groups such as al-Qaeda and the Islamic State probably fit the definition.

Myth No. 3

Leaking classified material or handling it sloppily is treason.

Shortly before Election Day in November, the Republican chairman of the House Homeland Security Committee, Rep. Mike McCaul, claimed that Clinton had committed treason by mishandling classified email. Edward Snowden has been denounced as a traitor for leaking classified documents, as have the intelligence officials who may have leaked damaging material about Flynn. The Conservative Daily Post pointed to "traitor moles nestled within the new admin."

But none of these actions amounts to levying war against the United States, as that offense requires some use of force in an attempt to overthrow the government. No such force or intent is present in any of these scenarios. Nor do the actions constitute aiding the enemy. Leaking information to newspapers is not providing aid to "enemies." This newspaper and others, whatever Trump might think of them, are not enemies of the United States. As with aid to Russia, such leaks might violate other provisions of federal law, but they are not treason.

Myth No. 4

Only U.S. citizens can commit treason against the U.S.

Even well-trained constitutional lawyers have sometimes repeated this myth. In his otherwise excellent book "Constitutional Faith," for instance, Sanford Levinson writes that treason "can be committed only by a citizen."

But the offense of treason can be committed by any person who owes allegiance to the United States, and this can include noncitizens. Treason law recognizes two kinds of allegiance: permanent and temporary. U.S. citizens owe permanent allegiance to the United States, and this duty carries with them wherever they go in the world. By contrast, noncitizens in the United States (other than ambassadors and their staffs) owe a duty of temporary allegiance, the Supreme Court found in an 1872 case. While they are within the United States and receiving protection from it, noncitizens are governed by American treason law. If a person on a green card or a student or tourist visa, for example, wages war against the United States or provides aid and comfort to our enemies, he cannot escape a treason prosecution simply by asserting his foreign citizenship.

Under this law, there is a strong argument that the 9/11 hijackers committed treason by levying war against the United States. When a noncitizen leaves the country, however, the duty of temporary allegiance disappears.

Myth No. 5

Very few Americans have committed treason.

No person has been executed for treason by the federal government under the Constitution. The small handful of people who have been convicted of the offense at the federal level — such as two militants from the Whiskey Rebellion and several people after World War II — have mostly been pardoned or released. So we are sometimes told that treason has been "rare" in the United States.

Hardly. During the American Revolution, the rebelling Americans were all committing treason against Britain. Similarly, the thousands of Americans who actively aided the British committed treason against the United States. In the Civil War, the hundreds of thousands of men who fought for the Confederacy all levied war against the United States, as did the people who aided and abetted the rebellion.

Neither the American Revolution nor the Civil War led to mass executions. At the end of the day, the spirit of reconciliation prevailed, and the victors allowed the vanquished to return home peacefully. But it remains the case that many Americans have a traitor lurking somewhere in their family tree.

clarson@ucdavis.edu

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