I don't think the point was missed. My personal belief is that you may be able to ticket it, but you may have some trouble if someone picks up on the routing. If the treasury department gets wind, they will care very little about a semantics argument relating to direct flights. What they will care about is that AA profited from a ticket that benefited the embargoed country, even if that benefit is in the form of landing fees. Then again, how would they find out? If you're this concerned, I would personally not take the flight. Go through Mexico City. I am sure you could find a reasonably priced flight from Cancun.