The new controversy about President Trump’s conduct toward the government of Ukraine is not really hard to understand, but it does involve multiple sub-issues. Here, then, in the interests of clarity, is a basic outline of the situation.

Sub-issue 1: Did Hunter Biden, son of the former vice president, engage in corruption while on the board of Burisma, an energy exploration company long operating in Ukraine; and did then-vice president Joe Biden improperly intervene to quash a Ukrainian government investigation of his son’s actions?