Who are famous celebrities who have served?

I knew about all of them except Hugh Hefner. Don't know too much about him. Here are several others (just a large drop in the bucket):

James Doohan
Clint Eastwood
Don Knotts
Tim Conway
Jack Palance
Humphrey Bogart
Charles Bronson
Sean Connery
Tom Selleck
John Derek
Steve Forrest
Gene Hackman
Chris Cooper
Michael Caine
Paul Newman
Carl Reiner
Buddy Hackett
Ernest Borgnine
David Niven
Jack Lemmon
Ice-T
Walter Matthau
Richard Attenborough
Montel Williams
Kirk Douglas
James Arness
Rod Stieger
Cesar Romero
Art Carney
Jack Warden
Lloyd and Beau Bridges
Blake Edwards
Rock Hudson
Anthony Hopkins
Carroll O’Connor
Gene Kelly
Lee Marvin
Dennis Franz
Richard Burton
James Whitmore
Charlton Heston
Sammy Davis Jr
James Garner
Tyrone Power
Ossie Davis
Eli Wallach
Roger Moore
Sir Alec Guiness
Rod Serling
James Coburn
Audrey Hepburn
Don Rickles
Steve McQueen
Donald Pleasance
Martin Balsam
Frank Capra
Anthony Quayle
Burgess Meredith
Mr. T
MC Hammer
Jason Robards
Robert Stack
Pat Sajak
Tony Bennett
Don Adams
James Best
Bob Keeshan
Charles Durning
Gene Autry
Eddie Albert
Burt Lancaster
Frank Gorshin
Julia Child
Brian Keith
Clark Gable
Alan Hale
George Kennedy
Benny Hill

Yes we all know Chuck went Air Force. The question is, why??

Drew Carey, USMC. Who knew?