In this statement Orson welles talks of the Justification in King Hamlet dethroning himself as King due to "matters of state".
Explanation:
King Hamlet's Spirit refers to hamlet's thoughts or decisions, the "King" is the position attached to the Person of 'Hamlet'. Therefore the writer is implying that due to a "matter of state" if Hamlet had taken the decision to dethrone himself, he would have been right.