This guy was comissioned as an officer in 1943, and retired in 1965...as a First Lieutenant? :@@:

I have never heard of anyone taking 23 years to be promoted just one rank. Either this is a typo, or there is something here thats extremely wierd

Please Read http://en.wikipedia.org/wiki/Vernon_Baker

One way it could happen would be that he left active duty after the war, but remained in the reserves. Promotions are notoriously slow in the reserves.

Some strange things happen with officers and their ranks. Those attending the service academies are commissioned "regular" officers. The ones attending Officer Candidate School, or receiving direct commissions are "reserve" officers. Following WWII and after the Korean conflict there was a vast Reduction in Forces (RIF). Those individuals (reserve officers) choosing to remain in the military were typically reduced in rank to that of NCO (Non-Commissioned Officer or Sergeant) with the understanding that they would retire at their permanant reserve rank when the time came.
When I was assigned to my first regular unit in 1969 I met NCO's that were WWII & Korean war vets that fell into the category I've described. Without the regulations at hand, it is rather difficult to explain properly.
Nothing I've read has given information on Lt Baker beyond a few paragraphs on his WWII service.