Bixby Letter is a decision available to 
USA while it is at war with 
Confederate States of America. It is usually taken during the Civil war, but it can potentially be used during other wars against the CSA. The Bixby Letter was sent from the President of the United States Abraham Lincoln to a widow Lydia Parker Bixby during the civil wars with condolences for her losing 5 sons during the civil war. The letter has since been used in many Civil war memorials.
It requires that USA has a War exhaustion of at least 6.0, and it reduces War exhaustion by 2.0 with no drawbacks.