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Twitter, Inc. v. Taamneh, 2023 U.S. LEXIS 2060, ___ S. Ct. ___ (May 18, 2023) (Thomas, J.). Thomas, J. delivered the opinion for a unanimous Court. Jackson, J. filed a concurring opinion. Justice Thomas delivered the opinion of the Court. Under 18 U. S. C. §2333, United States nationals who have been “injured . . . by reason of an act of international terrorism” may sue for damages. §2333(a). They are not limited to suing the individual terrorists or organizations that directly carried out the attack, however. That is because §2333(d)(2) also imposes civil liability on “any person who aids and abets, by knowingly providing substantial assistance, or who conspires with the person who committed such an act of international terrorism.” Victims of terrorist acts therefore may seek to recover from those who aided and abetted the terrorist act that injured them. The plaintiffs (who are respondents) contend that they have stated a claim for relief under §2333(d)(2). They were allegedly injured by a terrorist attack carried out by ISIS. But plaintiffs are not suing ISIS. Instead, they have brought suit against three of the largest social-media companies in the world—Facebook, Twitter (who is petitioner), and Google (which owns YouTube)—for allegedly aiding and abetting ISIS. As plaintiffs allege, ISIS has used defendants’ social-media platforms to recruit new terrorists and to raise funds for terrorism. Defendants allegedly knew that ISIS was using their platforms but failed to stop it from doing so. Plaintiffs accordingly seek to hold Facebook, Twitter, and Google liable for the terrorist attack that allegedly injured them. We conclude, however, that plaintiffs’ allegations are insufficient to establish that these defendants aided and abetted ISIS in carrying out the relevant attack. Those injured by an act of international terrorism can sue the relevant terrorists directly under §2333(a)—or they can sue anyone “who aids and abets, by knowingly providing substantial assistance, or who conspires with the person who committed such an act of international terrorism” under §2333(d)(2). For such a secondary-liability claim, there is an additional condition: The “act of international terrorism” must have been “committed, planned, or authorized by an organization that had been designated as a foreign terrorist organization under [8 U. S. C. §1189] as of the date on which such act of international terrorism was committed, planned, or authorized.” Ibid. Plaintiffs seeking secondary liability can likewise recover treble damages and the cost of the suit, including attorney’s fees. See §§2333(a), (d)(2). At bottom, the elements and factors of both JASTA (Justice Against Sponsors of Terrorism Act) and Halberstam v. Welch, 705 F. 2d 472 (CADC 1983) rest on the same conceptual core that has animated aiding-and-abetting liability for centuries: that the defendant consciously and culpably “participate[d]” in a wrongful act so as to help “make it succeed.” Nye & Nissen, 336 U. S., at 619, 69 S. Ct. 766, 93 L. Ed. 919. To be sure, nuances may establish daylight between the rules for aiding and abetting in criminal and tort law; we have described the doctrines as “rough[ly] simila[r],” not identical. Central Bank of Denver, 511 U. S., at 181. But we need not resolve the extent of those differences today; it is enough for our purposes to recognize the framework that Halberstam set forth and the basis on which it rests. The phrase “aids and abets” in §2333(d)(2), as elsewhere, refers to a conscious, voluntary, and culpable participation in another’s wrongdoing. To summarize the requirements of §2333(d)(2), the phrase “aids and abets, by knowingly providing substantial assistance,” points to the elements and factors articulated by Halberstam. But, those elements and factors should not be taken as inflexible codes; rather, they should be understood in light of the common law and applied as a framework designed to hold defendants liable when they consciously and culpably “participate[d] in” a tortious act in such a way as to help “make it succeed.” Nye & Nissen, 336 U. S., at 619, 69 S. Ct. 766, 93 L. Ed. 919 (internal quotation marks omitted). And the text requires that defendants have aided and abetted the act of international terrorism that injured the plaintiffs—though that requirement does not always demand a strict nexus between the alleged assistance and the terrorist act. None of those allegations suggest that defendants culpably “associate[d themselves] with” the Reina attack, “participate[d] in it as something that [they] wishe[d] to bring about,” or sought “by [their] action to make it succeed.” Nye & Nissen, 336 U. S., at 619,69 S. Ct. 766, 93 L. Ed. 919 (internal quotation marks ommitted). In part, that is because the only affirmative “conduct” defendants allegedly undertook was creating their platforms and setting up their algorithms to display content relevant to user inputs and user history. Plaintiffs never allege that, after defendants established their platforms, they gave ISIS any special treatment or words of encouragement. Nor is there reason to think that defendants selected or took any action at all with respect to ISIS’ content (except, perhaps, blocking some of it). Indeed, there is not even reason to think that defendants carefully screened any content before allowing users to upload it onto their platforms. If anything, the opposite is true: By plaintiffs’ own allegations, these platforms appear to transmit most content without inspecting it. In this case, it is enough that there is no allegation that the platforms here do more than transmit information by billions of people, most of whom use the platforms for interactions that once took place via mail, on the phone, or in public areas. The fact that some bad actors took advantage of these platforms is insufficient to state a claim that defendants knowingly gave substantial assistance and thereby aided and abetted those wrongdoers’ acts. And that is particularly true because a contrary holding would effectively hold any sort of communication provider liable for any sort of wrongdoing merely for knowing that the wrongdoers were using its services and failing to stop them. That conclusion would run roughshod over the typical limits on tort liability and take aiding and abetting far beyond its essential culpability moorings. As alleged by plaintiffs, defendants designed virtual platforms and knowingly failed to do “enough” to remove ISIS-affiliated users and ISIS-related content—out of hundreds of millions of users worldwide and an immense ocean of content—from their platforms. Yet, plaintiffs have failed to allege that defendants intentionally provided any substantial aid to the Reina attack or otherwise consciously participated in the Reina attack—much less that defendants so pervasively and systemically assisted ISIS as to render them liable for every ISIS attack. Plaintiffs accordingly have failed to state a claim under §2333(d)(2). We therefore reverse the judgment of the Ninth Circuit.