Respectfully, this apology is hard to take seriously, considering the detail and vitriol contained in his attack.
Yup - this doesn't quite qualify for an "Oops, I mis-spoke" retraction. He simply realized, based on the comments he received in response, that the threatened use of U.S. military armor and air power against civilians wasn't very smart.
Indeed, some responders seemed to relish the challenge. Swindell realized that he'd just dared some very capable rifleman to give him a high-velocity enema.