The second round of impeachment hearings started Wednesday, with the House Judiciary Committee obtaining testimony from a panel of constitutional and legal experts on the impeachable nature of President Trump's attempt to blackmail Ukraine into interfering in the 2020 election. They also repeatedly noted Trump's obstruction of the Mueller investigation.

Those are surely important things to establish, and are more than enough cause to throw Trump out of office. But so far it appears that the impeachment inquiry is going to remain narrowly focused on the Ukraine and Russia scandals, and thus leave a hugely obvious and damning aspect of Trump's corruption unmentioned — namely, his unconstitutional profiteering off the presidency.

This would be a terrible oversight.

As I have written previously, the Constitution categorically forbids the president from collecting money either from the U.S. government (aside from his salary) or from any foreign states. Article I, Section 9 states that no one "holding any Office of Profit or Trust" under the U.S. government can receive any kind of gift, payment, office, or title from any foreign state without the consent of Congress. Article II, Section 1 states that the president shall be paid a salary, but cannot receive any other payments from the U.S. government or any state governments.

The organization Citizens for Responsibility and Ethics in Washington has been keeping track of Trump's conflicts of interest, and found a sprawling labyrinth of corruption just from what is publicly available. As president, Trump has stayed at his own properties — complete with enormous presidential entourage — on the public nickel 362 times. At least 250 of his administration's officials have visited a combined 630 times. Ninety members of Congress have visited 180 times, plus 47 state-level officials who have visited 64 times. Representatives of 65 different foreign governments have visited 111 times. Trump has also publicly promoted these properties at least 159 times — thus using his prominence as president for his own profit — while his administration's officials have done so 65 times. Finally, his businesses have received 59 foreign trademarks during his time in office.

Again, it couldn't be more obvious why the framers of the Constitution set up these prohibitions. Half the point of setting up a democratic republic in the first place is to create a government that will treat high office as a public trust, not an opportunity to loot the citizenry — and they explicitly argued that any president who did so should be removed from office. During the debate over writing the Constitution, James Madison argued in favor of an impeachment mechanism, because in "the case of the Executive Magistracy which was to be administered by a single man, loss of capacity or corruption was more within the compass of probable events, and either of them might be fatal to the Republic." In Federalist #64, John Jay wrote that the idea of a corrupt president "is too gross and too invidious to be entertained," but "that motive to good behavior is amply afforded by the article on the subject of impeachments."

For all their flaws, the founders were absolutely right to be concerned about this. President Donald Trump is their worst nightmare, and as Wednesday's panel of expert witnesses would surely testify, a president who views all levers of power like the arm on a cash register is a disaster.

Both the Russia and Ukraine scandals are genuine outrages. But Trump's stupendous empire of graft is just as bad, and perhaps even easier to understand. Americans pay taxes with the expectation that the money is going towards the general public welfare, like Social Security or Medicaid. Of course there is plenty of shady dealing in defense contracting and elsewhere, but such instances fuel outrage when discovered because of how they violate this elementary principle. That is why corrupt contractors disguise what they are doing behind delivering some ostensibly-worthwhile service. A president simply stuffing public money — not to mention bribes from foreign states — directly into his pockets is a howling violation of foundational American principles.

It's also not like pursuing Trump's graft dilutes Democratic messaging on Ukraine. On the contrary, it fits perfectly with the picture of Trump as a totally unscrupulous grifter who will take absolutely any opportunity to advance his own narrow self-interest, whether it's trying to blackmail helpless foreign governments to help him politically, or lining his own pockets out of the government treasury.

It's honestly mystifying why Democrats aren't giving Trump's graft top billing next to the Ukraine story. Perhaps it's because matters involving so-called national security tend to be regarded by the mainstream press as more serious than the usual partisan dispute. Whatever the reason, Democrats should reconsider. Trump's graft is a grotesque violation of the Constitution, a moral obscenity, and a perfect way to deflate his "drain the swamp" rhetoric. It's a quick and easy way to add an open-and-shut case to any articles of impeachment.

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