Yeah. And Saddam Hussein could have dumped anthrax in our cities but didn't. Nevermind that he had used the stuff elsewhere before and nevermind that in all likelihood he was plotting to use it against us if he ever got the chance. I guess the fact that he never did means we had no basis to remove him from power, and I guess that it is only legitimate to remove a threat to you AFTER it has pulverized a couple of your cities and waged terroristic warfare on your people.
The fact is that the Fort Sumter garrison was a hostile army exercising hostile and threatening intent against the city of Charleston. Under the doctrine of preemptive war the people of Charleston had every right in the world to remove that threat.
What hostile and threatening gestures did the Fort Sumter garrison make?