On Tuesday night, Democratic presidential candidate John Edwards and Late Show host David Letterman spent a significant amount of time discussing Edwards' beef with FNC host Bill O'Reilly over the homeless veterans issue. Last night on the O'Reilly Factor, the host fired back against what the duo said (Bernie Goldberg and Jane Hall lent their opinion for the segment as well). Interestingly, O'Reilly hinted at a possible appearance on Late Show to defend himself: