By Jennifer Rubin – The Washington Post.

Sen. Claire McCaskill (D-Mo.) ran circles around Treasury nominee Steven Mnuchin on the topic of President-elect Donald Trump’s foreign holdings and debt held by foreign banks.

McCaskill got Mnuchin to acknowledge Trump will return to his businesses and reap the benefits accrued while he was president. She pressed him to promise to report on the percentage of his debt held by foreign banks. (He declined to promise, but he promised to talk to the president.) She queried him about whether Trump would be able to fire his so-called ethics officer. At another point in the hearing, citing her experience as an auditor, she noted that Trump promised to donate only profits from his hotels from foreign sources. What about income in a nonprofitable venture? He could not say. Who is going to audit these businesses to see if there is profit and whether it is traceable to foreigners? He had no answer.

Her questioning goes to the heart of the Emoluments Clause violation(s) that Trump will be guilty of upon taking the oath of office. Republicans shamefully have not asked, let alone demanded answers. They should do so before voting on Mnuchin or other nominees who are not related to national security.

Should Republicans refuse to hold hearings and/or demand answers from Trump to McCaskill’s questions, what is the recourse? Democrats could filibuster any and all legislation. They could run on the issue on 2018. And Congress always has the power of impeachment.

McCaskill showed us how little we know about Trump’s holdings, how serious potential conflicts with foreign governments are, and how dilatory Republicans have been in fulfilling their Constitutional obligations. If only Rep. Jason Chaffetz (R-Utah) would have the same enthusiasm for protecting the Constitution as he did for investigating Hillary Clinton, we might actually see some swamp draining.