Treasury Secretary Steven Mnuchin really wanted to talk about "the real issue of the week," Iran, on CNN's State of the Union Sunday, but Jake Tapper insisted they first discuss a growing scandal involving President Trump pressuring Ukraine's president to investigate former Vice President Joe Biden and his son, Hunter Biden. Trump's interactions with Ukraine are reportedly at the center of an intelligence officer's whistleblower complaint.

Trump has acknowledged bringing up the Bidens with Ukraine's president in the context of "corruption" — there's no evidence Hunter Biden did anything illicit when he sat on the board of a Ukrainian gas company, nor that Joe Biden intervened to help his son — but the White House denies that Trump was using $250 million in U.S. military aid as leverage.

Mnuchin and Tapper went back and forth about what Trump may or may not have said to Ukraine's president, whether it was appropriate, and whether the public has a right to know. Finally, Mnuchin said that what he finds "inappropriate is the fact that Vice President Biden at the time's son did very significant business dealings in Ukraine," and he thinks that issue perhaps "should be further investigated."

Tapper followed up: "So it is okay for Donald Trump Jr. and Eric Trump to do business all over the world, it's okay for Ivanka Trump to have copyrights approved all over the world while President Trump is president, but while Vice President Joe Biden was vice president, his son shouldn't have been able to do business dealings?" Mnuchin said he didn't want to "go into more of these details," and Tapper cut in: "Well, you're just setting a precedent that the president is violating."

Mnuchin said he sees "a significant difference" between the two situations, and Tapper finally moved on to Iran. You can read the entire transcript at CNN. Peter Weber