So what would be a winning strategy in this scenario?
I don't think there is one. So let him know you think he's an arsehole while you have the chance because nothing you can say or do is going to change the general's stance on this issue. He's above the law and completely unaccountable. But he's not beyond being called out for being a bad person by another person, and I suspect that's the closest you're going to get to justice on this issue.
Well, you have to be prepared, and think out the consequences. You should have some leaders who are used to acting disciplined in public protest.
If you choose to shout him down (e.g., for a messy and still-controversial example, http://en.wikipedia.org/wiki/AIDS_Coalition_to_Unleash_Power...) you'd better have a united message and a goal, and media present. And it might still be a bit of a mess. (I had the privilege of attending a lecture on organizing by one of the leaders of this action.)
Other choices are to turn your backs on the speaker, or to walk out en masse.
I'm not sure there was time to prepare for this one, because these revelations are so fresh.
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By the way, you seem pessimistic that this state of affairs can change due to grassroots action. I don't share your pessimism. When people find out the NSA has been scooping up their e-mail and Facebook chats?
I don't think there is one. So let him know you think he's an arsehole while you have the chance because nothing you can say or do is going to change the general's stance on this issue. He's above the law and completely unaccountable. But he's not beyond being called out for being a bad person by another person, and I suspect that's the closest you're going to get to justice on this issue.