"Establishing credibility" is an interesting concept I first heard from Noam Chomski on Pacifica Radio. I think the transcript is here>

Establishing Credibility

And the US doesn't want to present evidence because it wants to be able to do it, to act without evidence. That's a crucial part of the reaction. You will notice that the US did not ask for Security Council authorization which they probably could have gotten this time, not for pretty reasons, but because the other permanent members of the Security Council are also terrorist states. They are happy to join a coalition against what they call terror, namely in support of their own terror. Like Russia wasn't going to veto, they love it. So the US probably could have gotten Security Council authorization but it didn't want it. And it didn't want it because it follows a long-standing principle which is not George Bush, it was explicit in the Clinton administration, articulated and goes back much further and that is that we have the right to act unilaterally. We don't want international authorization because we act unilaterally and therefore we don't want it. We don't care about evidence. We don't care about negotiation. We don't care about treaties. We are the strongest guy around; the toughest thug on the block. We do what we want. Authorization is a bad thing and therefore must be avoided. There is even a name for it in the technical literature. It's called establishing credibility. You have to establish credibility. That's an important factor in many policies. It was the official reason given for the war in the Balkans and the most plausible reason.