agnosticism means not knowing. It makes no statement about belief.
atheism means not believing in a theos, or god. It is the absence of a belief in a god. It is not a belief that there is no God. and It is certainly not an assertion that someone can prove that there is no God, or that it is certain that there is no God.
agnosticism and some belief systems can go together, if the belief systems do not claim any knowledge.
agnosticism and the simple nonbelief of atheism also can go together, very well.
people have additional opinions and beliefs, which can be added to agnosticism or atheism, but these are not essential to it.
for example, I am an agnostic and an atheist, as I define them. I add a few words to the atheist part - I do not believe in any God THAT I have ever read about heard about imagined. I do not go so far as to say that I do not believe in any God that I have not read about heard about or imagined. That would be silly, mostly. just as silly as believing that there is one.
as an agnostic, I go beyond that and doubt that many cosmic-type questions can be answered, or even are rationally answerable - for reasons of non-evidence, and also for reasons of an incorrect foumulation of the questions.
I actively do not believe in or approve of the Biblical God, and this is an extra opinion that I have, and not atheism per se.
I certainly do not accept the notion that the only concept of God one is discussing is the monotheistic one of an all good, all powerful, and all knowing God. I actively disbelieve in such a god, because of the problem of evil. That in itself does not make me an atheist.
I think there is no necessary connection between ethics and theology. One can have a kind ethics with or without religious views, and an unkind ethics with or without religious views. I believe in an ethic of what I call informed kindness - good intentions are not enough. Lots of information without good intentions is also not good enough. Both without action are not good enough - although some times one does not seem to have the power or ability to act. I do not know how to save all the stray cats and dogs in the world. I wish I did. I do not think I am immoral because I cannot. I think that I am nearly broke because of how much I have already tried, however.
I think it is child abuse to teach children some versions of religion, predominantly religious with the notions of sin and the need for salvation and the danger of going to hell if one does not do this or that or believe this or that. Those are scare tactics, to enforce obedience and discourage rational thought. The doctrines are anti-love, yet often taught with the appearance of love. Those who try to bind children to doctrines that are very unloving often were taught the same things themselves, and do not know better.
It is better to have a reasonably tolerant view toward the beliefs of others, if they stay beliefs and concepts, and do not lead to a horrible ethic. if they lead to a horrible ethic, then it is often necessary to go to the root of the problem, in the disgusting theology. The notion of original sin, of salvation by belief, of hell for non-believers, of a rapture for believers, of an armageddon and last days and a final battle - are all part of disgusting theology and often lead to horrible ethics, particularly political and international opinions - such as not caring about possible global warming or nuclear proliferation, wanting to have a war in the place some folks think is predicted in some part of the Bible, to trigger the last days etc, and blaming the victim for anything that happens to him.
This may help start a discussion, and if anyone wants to read the comments after the article, well on a hot day outside, if you are cool enough, go ahead and spend your time that way if you wish.