Either way he isn't telling the truth. Many people don't seem to think so. Conservative web sites were abuzz last week with veterans putting forward the disturbing argument that executing defenseless noncombatants is the sort of thing warriors are driven to do. Those of us who never served are warned not to judge what we cannot understand. This is pernicious nonsense.
Moral judgment is everybody's right and responsibility.
We can't just wink at every atrocity committed under our flag. War is a moral minefield and our military ethics are not rigidly consistent. We tolerate civilian casualties inflicted en masse from the air but not those deliberately inflicted at ground level with a gun or a knife. Humans are not rigidly consistent creatures. If there is proof beyond reasonable doubt that Bob Kerrey is a murderer he should be tried and punished.