Here is the opinion in United States v. Hamdan, a companion case to al Bahlul (the opinion for which is still pending): Hamdan Opinion.

Hamdan, you may recall, was the subject of a major U.S. Supreme Court ruling a few years back, Hamdan v. Rumsfeld.

Here is the relevant text from the opinion (starting on page 52, 53, and concluding at page 63):

2. 19th Century Irregular Warfare and Aiding the Enemy

In 1818, during the first Seminole War, General Andrew Jackson and the U.S. Army entered Florida, which at that time was neutral Spanish territory, in pursuit of Indian warriors. David Glazier, The Laws of War: Past, Present, and Future: Precedents Lost: The Neglected History of the Military Commission, 46 Va. J. Int’l L. 5, 27 (2005) (citations omitted) Two British citizens, Arbuthnot and Ambrister, were aiding the Indian warriors. Id. (citation omitted). Following their capture, a special court,117 military commission,118 or court-martial119 was convened to try the two men. Arbuthnot was found guilty of, “Charge 1st. Exciting and stirring up the Creek Indians to war against the United States. . . [and] Charge 2d. [A]iding, abetting, and comforting the enemy, supplying them with the means of war,” and he was sentenced to hang. Glazier, supra n. 113, at 28 (citations omitted). Ambrister was convicted of, “Charge 1st. Aiding, abetting, and comforting the enemy, supplying them with the means of war, he being a subject of Great Britain, at peace with the United States, and lately an officer in the British colonial marines. . .” and, “Charge 2d. Leading and commanding [Indians], in carrying on a war against the United States.” Id. at 28 (citing Minutes of the Proceedings of a Special Court, H.Q. Div. of the South at 154-55, 164; H.Q. Div. of the South, G.O. (Apr. 29, 1818)). Colonel Winthrop criticized General Jackson for approving a harsher sentence than the tribunal adjudged on reconsideration.120 Birkhimer, however, considered General Jackson’s actions to be lawful in every respect.121 Winthrop did not criticize the decision to charge Arbuthnot and Ambrister with aiding the enemy. 1920 Winthrop, supra n. 23, at 464-65.

The court takes no comfort in the historical context in which these events occurred or the ultimate disposition of these cases. We cite to these events for their historical occurrence as an embryonic effort of the United States to deal with the complexity of fighters in irregular warfare. In contrast, under the 2006 M.C.A., AUECs have significant due process and are not subject solely to the discretion of the executive. See n. 171 infra.

***

As Attorney General Speed explains at p. 58, ante, the offense against the law of war is complete when these individuals joined the guerilla band. Of course, some action is usually required to manifest that they have joined the guerilla band, such as “taking up arms,” providing advice on how to destroy trains or telegraphs, or providing their presence on a raid. See p. 58, supra. A person can also violate the law of war by providing assistance to a guerilla band, and Civil War military commissions punished numerous offenders for providing a wide array of such assistance. These examples of Civil War-era military commission convictions for providing support or aid to insurgents and guerillas illustrate the long-standing prohibitions against conduct similar to appellant’s aid to al Qaeda.

(red emphasis ours).