Well, we can start with my view of morality. My view is that the only actions that are immoral are those that cause injury to another person or their property without their consent.
This belief system is based on thousands of years of human history showing what is required for a society to survive and prosper. The existence or non-existence of supernatural deities is wholly immaterial to my view of morality.
thousands of years of human history...or millions??
Using your standard of 'morality,' any human being can come up with his or her own standard of right and wrong, as well as what 'hurts' another human being, right?
NAMBLA claims that man/boy sex doesn't hurt anyone. Who's to say that their opinion is wrong?
Fortunately, the Founding Fathers didn't take such a liberal view of morality as you do, and understood that it came from the Creator.