In the good old days, the US could retaliate against a terrorist country for a terrorist act against the US or a US citizen. If we got it wrong, nobody knew except for the real perpetrator and, possibly, us. If someone credible spoke out, we would have a new target.
While thinking about the War on Terror, I realized that, if we have a list of “bad guys/countries”, we can pick a (deserving) target and punish them. Everybody will think that crime does not pay except for the real perpetrator.I can see an analogy with local law enforcement. Now, with DNA evidence, the innocent of the particular crime is being set free but no replacement is being found.