Do you apply sinister motives the the US government in regard to the terrorist attacks that were perpetrated against us?
If you aren't implying sinister motives, then do you admit that the perpetrators of the attacks should be harshly dealt with?
Do you think the fact that the FBI didn't/couldn't stop the attacks, for whatever reason, means that we shouldn't respond to such attacks?
If you think we should still respond, why would you claim the missions designed to punish the groups responsible for those attacks are "missions that seemingly have no purpose"?