Human rights? We would like to think we care, and we don't.
Punishment for use of WMDs? IF it happened, we sold gas to Saddam. And the means to spread it.
Establishment of a friendly regime? Friendlier than Assad?
Keep the Russians out of the area? Maybe.
Keep the Chinese out of the area? Maybe, if they're interested.
Maintain our respected position as the worlds' policeman? Nope.

What would we get for our intervention?
Thanks from the Syrians? What's the history on that?
Thanks from the ROW? Probably not, and if so, so what?
A friendly ally in the area? Nope.

There's no excuse for doing anything, and there's no gain for it.
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