That Jimmy Carter has a strong opinion about George Bush is not offensive. No big deal.
That Jimmy Carter wants to pass off any strong reaction to his strong comments as "maybe misinterpretation," which implies that the listener got it wrong, is odorous.
Interviewed on the TODAY Show about the comments, Carter said, "They were maybe careless or misinterpreted." He said he "certainly was not talking personally about any president."Emphasis mine.
When pressed by NBC's Meredith Vieira as to whether he was saying his remarks were careless or reckless, the former president said, "I think they were, yes, because they were interpreted as comparing this whole administration to all other administrations."
Ah, it's you, see. The one listening who is the problem. You interpretted the comments poorly.
Either belly up to the bar and speak it out, or don't, but if you put it out there, don't crawl away from it by blaming it on a misinterpretation by those who heard you when you said, "I think as far as the adverse impact on the nation around the world, this administration has been the worst in history." How can anyone misinterpret that? He was blatantly "comparing this whole administration to all other administrations."
Never blame the listener for hearing your clear comments as you gave them. You come across as an egotist and a buffoon. You either misspoke. Or you said something you shouldn't have said publicly. But misinterpretation on the part of your listeners is not the error of your words.