Charlie Sheen was originally set to play the role of Sergeant Ron Kovic in the film "Born on the Fourth of July," but Tom Cruise ended up taking the role. Sheen felt hurt that the director, Oliver Stone, didn't even call him to inform him of the change. The role became a turning point for Cruise's career, earning him his first Oscar nomination and showcasing his acting abilities. Some experts believe Sheen could have been equally impressive in the role, given his talent and previous successful films like "Platoon" and "Wall Street." However, Sheen's personal issues, including substance abuse and allegations of violence, hindered his career. Despite the missed opportunity, Cruise continues to thrive in the industry while Sheen's path has been marred by shame and anonymity.