How do we see political strife and power struggles in Much Ado About Nothing?

One of the most common themes in Shakespeare's plays is the political strife between a rightful ruler and those who challenge that rule. We see it most clearly in Macbeth, Richard II, and several other history plays, but Shakespeare also explores it in Much Ado About Nothing in the form of Don John, the illegitimate brother of Don Pedro, who attempts to create distrust between Don Pedro and his most loyal followers and friends. The illegitimate son or brother becomes almost a stock character in Shakespeare—he cannot be trusted; his only goal is to sow discord in an otherwise peaceful reign; and he has few, if any, redeeming virtues. The subtext here and in other plays is that rightful rulers or leaders must always be aware of attempts to destroy their rule.