I hope Obama keeps his mouth shut until SK reveals their response. We are not the world police and it's not our place to keep Il's hands off of the south. We are South Korea's ally, and we should support them in whatever action they take, but we should not take the lead. If the South decides to wuss out and let this slide, we wouldn't want Obama beating the war drums only to find that no war is forthcoming. Similarly if he sits there pledging sanctions and such only to find out that South Korea has decided on a full out invasion, we'd end up looking weak. For the moment we should do exactly what we're doing - stand behind the findings of the investigation and pledge our support for South Korea.