he was a terrible actor
He was an actor for his time, gave them what they wanted for the buck, did have three decent roles, Quiet Man, Red River, and the Searchers, the vast majority of the rest of his work was the same character in different scenarios, he even played Orientals with an American accent
As I side note, just like we have actors today get up and diss the President I can remember Wayne doing the exact same thing in his time except from the right. Remembering questioning its appropriateness at the time puts today's condemnations in a different perspective

