Bob Greene: Report on classified papers exonerates the president of any criminal accusation. Greene: But the report damages him politically by focusing on his age and mental acuity.

He says Biden's memory was “significantly limited,” that he showed “diminished faculties” Greene: Biden tried to demonstrate that he is mentally fit: “I am well-intentioned and I am an older man’“ Greene: With a broken voice, he pointed out that he carries a roary’s son, who died in 2015 from cancer.