That's dishonest in itself. People do bad things they think are good without religious cause. The invasion of Iraq is a stellar example and while Bush may think he was anointed there were a great many atheists who were chomping to eliminate the supposed threat of Saddam and rescue the world from terrorism. Didn't work out that way. You don't get to assign values, sorry. Good people can do bad things because they think their leader, their political ideology is superior and therefore they are right. It's indistinguishable from religion in that regard.
As far as "the heart of atheism" there really isn't one. There is no moral core in any sense involved in it. Religion is a motivator. Some of it is good, and some is bad. Atheism is nothing at all, and how can it be otherwise, unless you believe that roaming groups of atheists go around doing good because they are atheists. There is no morality, no good, no evil, nothing at all in it. That doesn't keep anyone from doing good or evil, and they can do as much with their "ologies" as much as others with their religion.
Ultimately one chooses action, or a lack thereof, and there are a whole host of reasons for it, some quite pathetic but hardly unique to any philosophy.
