My agreement is not with gdani but tsomer. My apologies for reversing the order, although I am sure it was clear by the end of the post anyway.
One further point. Assume for the sake of argument ATS applied (which I do not believe is the case). The interaction between tort law and constitutional law is not one of artificial compartmentalization, but of seamless integration. An American citizen, at least in theory, cannot be condemned in tort *by an American court* for exercising a fundamental constitutional right, even if such action is disapproved by a foreign or international body of law.
Furthermore, it is a given that Ugandan law is not the issue, i.e., has not been breached by Lively. The only possible basis is international law, which is basically treaty law, including any relevant UN agreements or “understandings,” and so falls under the precedent of Reid v Covert and similar such cases, which have uniformly recognized positive, fundamental constitutional rights as superior to and unaffected by treaty.
So you cant keep free speech out of it. Tort law requires there to be a duty, a breach of that duty, and a causal, legally proximate relationship between that breach of duty and some real harm in consequence. For Americans under the First Amendment, there is no duty to hide ones viewpoint due to hypothetical harms that may or may not result. Falsely shouting fire in a theatre is not expression of a viewpoint, but a reckless or perhaps malicious misrepresentation of physical facts. Stating that a government should discourage social and legal accommodation with homosexuality, on whatever grounds, is viewpoint expression, and that is protected, and could never be reasonably considered a breach of duty under tort.