(CNN) Earlier this week, a federal judge ruled that a lawsuit alleging that President Donald Trump is violating the emoluments clause in the Constitution -- essentially profiting from his office via his Trump International Hotel in Washington -- could move forward. Emoluments aren't something the average person knows about, and most people aren't following this story closely. But the lawsuit has the potential -- emphasis on "potential" -- to force Trump to divest himself totally of his various business interests or walk away from the White House. I reached out to Georgetown Law professor John Mikhail, who has done considerable scholarly work on emoluments, to explain why they matter and whether this ruling poses a real threat to Trump.

Our conversation, conducted via email and lightly edited for context, is below.

Cillizza: Define "emolument." And explain why we are talking so much about this when it comes to Donald Trump's White House.

MIkhail: When the Constitution was written, "emolument" was a flexible term that generally meant "profit," "gain, "advantage," or "benefit." It was commonly used in ordinary English to refer to advantages or benefits of different types. For example, government salaries, payments on a contract, the interest on a loan, and the profits from ordinary commercial transactions were all referred to as "emoluments." So, too, was the rental income earned by churches, halls and boarding houses.

People are talking so much about emoluments now because there is a clause in the Constitution that forbids federal officials from receiving emoluments -- that is, profits, advantages or benefits -- from foreign governments without the consent of Congress. Since the start of his presidency, Trump has been doing just that. As a result, several lawsuits have been brought against him in order to stop these constitutional violations.

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