(This was originally a reply to https://news.ycombinator.com/item?id=32934936, which originally had a title implying that.)

Do we have any proof it's Meta doing this, as opposed to the Iranian government blocking Whatsapp within its borders?

(As much as I dislike Meta —) applying foreign laws to foreign users isn't "dealing" with the Iranian government. "Dealing" in the legal sense generally requires a two-way exchange. If Iran unidirectionally imposes a regulation, that's not a deal; Meta has made no decision to enter into it.

(Reference/entry point for legal aspects about this: contracts are also invalid if they're purely unidirectional. If I remember correctly there's a LegalEagle YT video about this, but you can probably dig this up elsewhere too.)

Possibly. Sanctions law is a hot mess of sometimes contradictory exceptions. In this case, the exceptions regarding "informational materials" may apply.

https://www.lawfareblog.com/did-twitter-violate-us-sanctions...