Go read those resolutions. You don't like the way they are worded, ok, please show me where in the Constitution it defines how the authorization for war should be formatted when they type it out...?
The issue of war on terror, oh please. What would you suggest then? The 9/11 hijakers weren't part of any state. Should we have declared war on every nation they hailed from? I believe that would have been Saudi Arabia, Lebanon, and Jordan.
Back to the topic, Chris Kyle, he did nothing wrong. We can have this silly debate over whether it's "constitutional" for Congress to make war against "terrorism" instead of a "nation," but what does that have to do with Chris Kyle? He's a war criminal because he didn't get your personal blessing?