Hanks is quite involved in the National WW2 museum that is located here in New Orleans. He was recently in the city to screen a preview of the HBO miniseries The Pacific. He is the executive producer. There was a reception after at the National World War II Museum.
He also narrates a documentary on the war that plays daily at the museum.
http://www.nola.com/movies/index.ssf/2009/11/world_war_ii_museums_beyond_al.html
None of this means that he is an expert on the war, but I thought I would post this as a point of interest to the thread subject.
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