I think the short answer to that is "yes". I think it is definitely possible for either atheists, agnostics, or people of any religion to have....or not have...a strong moral sense and a clear understanding of right and wrong.

I say this because I've seen moral and immoral people in all those general categories. The main question is: can they empathize with and love and respect others? Do they have enough self-esteem to honor themselves and others? If so, they probably have a pretty good sense of morality.

Most morally strong people decide what is right or wrong one of two ways:

1. by following a predetermined set of moral rules (the passive way. Doesn't involve much independent thought)

2. by following the Golden Rule, which is.... "Do unto others as you would have them do unto you...and also...don't inflict upon others what you would not want inflicted upon you." This means allowing others the same freedom and autonomy and consideration and kindness that you yourself desire. (the active way. Involves much independent thought.)

It's pretty simple really. The active way is definitely a more enlightened path, in my opinion.