Oh, even more reason for Jon to have wanted Daenerys dead!
Fair enough; I'll concede the point of Aemon's age.
No, he does look quite foolish if he dodges a question--we see time and time again that it's a very commonplace thing for rulers in Westeros to make pointed questions against their "betters" with the expectation that the question be answered. Further, I should think that the lord would have to be very thick to not see the insult Aemon made against everyone in the room except Aerion. House Tyrell is literally the most powerful House man-for-man in the Seven Kingdoms. Unless you speak to House Tyrell from the perspective of wealth or perhaps age, there is no station that can be inhabited by another House of the Seven Kingdoms (save Targaryen) that House Tyrell cannot occupy. Ergo, you're literally telling every other House in the Seven Kingdoms that they aren't worthy of you. And for those especially thick lords that don't realize, Loras would do well to emphasize that point.
If Aemon is seized and executed than the imminent Arryn-Stark-Tully rebellion won't have enough power to overthrow the Tyrell-Lannister-Targaryen faction. It would go far to strengthen Aerion's reign, actually, than to harm it--assuming he wins, of course. And, as to the matter of kinslaying . . . it might be simpler that Aemon died in the night of a "sickness", and was not executed.
I further concede the point of a hypothetical invasion. It is rather mute.






alright then.