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Rh assistance to Welch’s activities by helping him turn his “stolen goods into ‘legitimate’ wealth,” thereby intending to help Welch succeed by performing a function crucial to any thief. Ibid. And it clarified that Hamilton knew Welch was committing some sort of “personal property crime,” the “foreseeable risk” of which was “violence and killing.” Ibid. The court therefore concluded that Hamilton substantially helped Welch commit personal property crimes and was liable for Halberstam’s death, which was a foreseeable result of such crimes. Ibid.

That articulation of the common law thus resolved Halberstam. But Halberstam recognized that the elements and factors it provided could “be merged or articulated somewhat differently without affecting their basic thrust.” Id., at 478, n. 8. It thus cautioned—in a typical common-law fashion—that its formulations should “not be accepted as immutable components.” Id., at 489. Rather, Halberstam suggested that its framework should be “adapted as new cases test their usefulness in evaluating vicarious liability.” Ibid.

The allegations before us today are a far cry from the facts of Halberstam. Rather than dealing with a serial burglar and his live-in partner-in-crime, we are faced with international terrorist networks and world-spanning internet platforms. By Halberstam’s own lights, its precise thre-eelement and six-factor test thus may not be entirely adequate to resolve these new facts. Ibid. And JASTA itself points only to Halberstam’s “framework,” not its facts or its exact phrasings and formulations, as the benchmark for aiding and abetting. §2(a)(5), 130 Stat. 852. We therefore must ascertain the “basic thrust” of Halberstam’s elements and determine how to “adap[t]” its framework to the facts before us today. See 705 F. 2d, at 478, 489, and n. 8. To do so, we turn to the common law of aiding and abetting upon