Can atheists rationally ground objective moral values and duties?

Here’s Dr. William Lane Craig explaining why atheists can’t help themselves to objective morality, given a worldview of atheism:He presents 3 reasons why in the video, all of which are also discussed in his Defenders class:The mention of Plato brings to mind another possible atheistic response to the first premise of the moral argument that if God does not exist, then objective moral values and duties do not exist. Plato thought that the Good just exists as a sort of self-subsistent