Before Donald Trump became president of the United States, we had a relatively simple understanding of government corruption. It’s as old as government itself: officials using their positions of public trust to benefit themselves and their associates. Preventing it seemed relatively straightforward.

But Trump has taught us that it’s more than that. He has offered us a corruption master class, presenting for our edification a kind of full-spectrum corruption that may be unprecedented in American history.

In doing so he has revealed that opportunities for corruption are far more numerous than we knew, which means that we’ll need a sweeping reexamination of the systems we put in place to prevent it.

Let’s examine some of the many flavors of Trump’s corruption, using stories that have emerged just in the past few days.

Personal self-dealing. As The Post reports, Trump has shown a remarkable commitment to using his properties to direct taxpayer money into his own pocket. He has visited those properties more than 280 times as president, each visit an opportunity to bill the government for food, lodging and facilities, in amounts running into the millions of dollars. No opportunity to grab some taxpayer cash is too small, down to the $3 per glass of water charged for a meeting with the prime minister of Japan.

Using government resources to promote his reelection. House Democrats have released documents on a $250 million ad campaign the Department of Health and Human Services had been planning to run to “defeat despair” during the coronavirus pandemic, bolstering one of Trump’s core reelection messages, that the pandemic is nothing to worry about.

In one meeting in September, the HHS official and Republican operative overseeing the effort suggested that “Helping the President will Help the Country” should be the theme of the campaign. It involved recruiting celebrities to record public service announcements, but they vetted these celebrities in part “based on whether they had ever criticized the president.”

Poisoning federal agencies with far-right ideology. The New York Times reports that the National Oceanic and Atmospheric Administration has seen a crackdown on scientists and public servants who accept the truth about climate change. When the agency’s acting chief scientist asked political appointees to acknowledge the agency’s scientific integrity policy, he was immediately removed. Climate deniers are being installed in top positions, and the department will now require that internal and external communications be reviewed in advance by political appointees to make sure they align “with the overarching guidance from the White House and Department.”

Purging civil servants. The White House has waged what Post reporters describe as “an unwavering four-year war on the civil servants who have operated as the backbone of the federal government for more than a century.”

In his latest move, Trump issued an executive order to strip civil service protections from tens of thousands or even hundreds of thousands of workers, allowing them to be fired if they are deemed insufficiently loyal to him. Many in senior roles throughout the government, including scientists, lawyers, regulators and health experts, could lose due process rights and even union representation. One high-ranking official resigned in protest, lamenting this effort to “replace apolitical expertise with political obeisance.”

Twisting government functions to his own personal ends. The Times scoops that a criminal case against a state-owned Turkish bank, one involving fraud and violation of sanctions on Iran, became the subject of personal lobbying from Treasury Secretary Steven Mnuchin, Attorney General William P. Barr, and Trump himself. All of them pressured the high-level prosecutor on the case to essentially let Halkbank off with a slap on the wrist; that prosecutor was eventually fired.

Turkish President Recep Tayyip Erdogan had urged Trump to let the bank off the hook; perhaps he rightly assumed that the help would be lubricated by Trump’s financial interests in Turkey and his pathetic desire to please every authoritarian strongman he deals with. Though the case is still pending, there are many others where Trump and Barr have successfully turned the Justice Department into Trump’s personal law firm.

To repeat, those are stories that emerged just in the past week; there are dozens, even hundreds more we could mention.

You might be forgiven for failing to predict all this. Yes, he’s long been one of America’s shadiest businessmen, a literal con artist who cheated on his taxes, stiffed his vendors, ran out on his debts and scammed people out of their life savings. But it was possible to tell yourself that despite all that, he might not run the presidency like one more grift, with the American people as the marks.

Perhaps he would be moved by the majesty of the office and the seriousness of the task to act with some shred of ethics or morality. And perhaps our institutions and laws were robust enough to resist his venality.

Four years later, while the stench of Trumpism pervades the entire federal government and decontamination will be a years-long process should he lose the election, the structure still stands. But as for Trump himself, he’s still every bit the same immoral swindler he was before he took office.

In the wake of this presidency, we’ll need a new approach to constrain any future President Trump (sorry if I just made you spit out your coffee). It will probably have to turn norms into strict rules, and provide genuine punishments for those who transgress. And it may involve limiting the authority of the president.

We’ll have to do it, because Trump has shown us how wide and deep corruption can go. And it’s only been four years; imagine what he could do with four more.

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