Er, he didn't apologize. His supposed apology stated that he was sorry that so many misunderstood his comment. That's not an apology. It's a statement that there are many people in America stupid enough not to understand his nuanced approach.
A real apology would have been 'I'm truly sorry I made a statement that was taken as a slap at our military. That was not my intention and I am very sorry for misspeaking'. There's a world of difference between the two.
Also, this has nothing to do with forgiveness. It has everything to do with holding a politician accountable for his ways.
ditto
That would not be a real apology. That would be a lie, since his slap at the military was clearly intentional.
A real apology would be "I'm sorry I've had such a negative attitude toward the military over the years. I hadn't realized how much good they actually do." It would have to be coupled with a continued demonstration of good will toward the military. Most likely, Sus scrofa will develop wings long before Kerry makes a real apology for his statements.