The distinction between action and inaction, to a significant degree, is artificial. There is really only one thing: the decision of the actor; there is no dichotomy. When viewed this way, you might not want to always call the outcome
fault, worthy of blame, but it is certainly forseeable consequence.
In the original OP, we are given the example of Spider-Man having to choose between Gwen Stacy and New York. We are told that when Spider-Man chooses New York, he is not responsible for Gwen's death. But this example takes the easy way out, and thus comes to the wrong conclusion about why Spider-Man is not to blame. If Spider-Man instead chose Gwen Stacy, and New York was destroyed, given that Spider-Man had a chance to stop it, he would be
entirely his fault that he did not take that chance. He would not be culpable for New Yorkers murders, but he would be for their deaths. The second is less bad than the first, but it is still really bad. Similarly, he would be responsible for having not saved Gwen Stacy (though not for murdering her). But given the situation his, the reason we do not place blame on Spider-Man is because
he obviously made the right decision. Making the right decision, while not enough to resolve you of legal sanction in all situations, is always going to cast you in a better light.
I cannot say I entirely understand the Japanese mindset, but if they are saying that you are responsible for that persons unforseeable actions, well, that is just so much worse for their ethical outlook (though that they are more likely to hold people responsible for forseeable consequences, then that may still be a plus for them).
In any case, I would say Iago was definitely complicit in Othello's actions. I think you could call him something of an "accessory to the crime" , or call him on "conspiracy to commit a crime" , or a related charge. In any case, should anyone decide to disagree with me, that is their prerogative, but my long-time signature affords me arbitrary levels of authority on this matter, so you will be wrong,

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