Why was John Yoo wrong?

Here's the language in Hamdan v. Rumsfeld that finds that Common Article 3 is applicable to Al Qaeda:

Alternatively, the appeals court agreed with the Government that the Conventions do not apply because Hamdan was captured during the war with al Qaeda, which is not a Convention signatory, and that conflict is distinct from the war [***14] with signatory Afghanistan. The Court need not decide the merits of this argument because there is at least one provision of the Geneva Conventions that applies here even if the relevant conflict is not between signatories. Common Article 3, which appears in all four Conventions, provides that, in a "conflict not of an international character occurring in the territory of one of the High Contracting Parties [i.e., signatories], each Party to the conflict shall be bound to apply, as a minimum," certain provisions protecting "persons . . . placed hors de combat by . . . detention," including a prohibition on "the passing of sentences . . . without previous judgment . . . by a regularly constituted court affording all the judicial guarantees . . . recognized as indispensable by civilized peoples." The D. C. Circuit ruled Common Article 3 inapplicable to Hamdan because the conflict with al Qaeda is international in scope and thus not a "conflict not of an international character. " That reasoning is erroneous. That the quoted phrase bears its literal meaning and is used here in contradistinction to a conflict between nations is demonstrated by Common Article 2, which limits its [***15] own application to any armed conflict between signatories and provides that signatories must abide by all terms of the Conventions even if another party to the conflict is a nonsignatory, so long as the nonsignatory "accepts and applies" those terms. Common Article 3, by contrast, affords some minimal protection, falling short of full protection under the Conventions, to individuals associated with neither a signatory nor even a nonsignatory who are involved in a conflict "in the territory of" a signatory. The latter kind of conflict does not involve a clash between nations (whether signatories or not). Pp. 65-68. [italics by Spot]

Tags: John Yoo, Geneva Conventions