Donald Trump has notched up some truly impressive achievements in the first 100 days of his presidency. We’re not talking about the humdrum stuff of other presidents. All those pesky to-do lists are far too conventional for this out-of-the-box thinker.

How unconventional is his thinking? It’s best if we leave it to the great man to explain this, as he described to the Associated Press the awesome nature of his presidency.

“Well the one thing I would say – and I say this to people – I never realized how big it was,” he said, when asked how the office has changed him. “You know the orders are so massive … Number one, there’s great responsibility. When it came time to, as an example, send out the 59 missiles, the Tomahawks in Syria, I’m saying to myself, ‘You know, this is more than just like 79 [sic] missiles. This is death that’s involved.’ Because people could have been killed.”

If this is what Trump has learned in 100 days, imagine the frontiers of knowledge he will explore by his 200th day in office. These missiles – 59, 79 or even 99 – can indeed kill people. Some people think that’s the purpose of Tomahawks.

These presidential decisions are indeed big, or massive or humungous. And Trump’s 100-day list will not be constrained by the smallness of past presidents or his own past promises, for that matter.

“I’ve done a lot,” Trump told the AP. “I’ve done more than any other president in the first 100 days and I think the first 100 days is an artificial barrier.”

In his first 100 days, Barack Obama passed a $787bn stimulus act, legislation on fair pay for women and expanded healthcare for children. His approval rating was 65%, compared to Trump’s 41%, which happens to be the worst 100-day rating for any president since Gallup began polling. Trump’s numbers are even worse than Gerald Ford’s after he pardoned Richard Nixon in his first 100 days.

But such comparisons do not truly capture the momentous nature of Trump’s presidency. The standards of other presidents lose all meaning alongside this small-time businessman with a track record of bankruptcy.

Candidate Trump spelled out his 100-day plan just 18 days before his world-rocking election victory – and did you know how incredible that victory was? Because if you don’t, the president would like to talk to you personally.

In a speech at Gettysburg, no less, the candidate promised to introduce the End Illegal Immigration Bill to fund the border wall, force Mexico to pay for it and lock up repeated offenders who cross the border without papers. He also promised to deport 2 million criminals (who just happen to be undocumented immigrants), renegotiate Nafta, cut taxes and repeal Obamacare.

Let’s start with immigration, shall we? Deportations are actually down 1.2% this year. Immigration-related arrests are up 32%, but a quarter of them have scooped up people with no criminal record at all.

The Muslim travel ban has failed repeatedly in the courts, along with Trump’s efforts to punish sanctuary cities. After 100 days in office, Trump’s border wall remains less real and formidable than Taco Bell’s double-stacked taco, which may also be more effective at deterring immigration from Mexico.

Trump tried and failed to repeal Obamacare. He’s talking about trying again, just like he’s talking about Nafta and talking about tax cuts. His administration talks a lot like a timeshare sales team, making wild promises to a captive audience in what amounts to a high-pressure pitch for distressed assets.

This may be a familiar feeling for the victims of Trump University, but it’s a new experience for the American people at large, and can thus be counted as another landmark of the first 100 days.

At a special press briefing on the one-page tax plan released on Wednesday, two formerly senior Goldman Sachs executives explained how the sketchy tax cuts would work. Standing alongside Gary Cohn (now Trump’s chief economic adviser), Steve Mnuchin (now US Treasury secretary) delivered the kind of argument that would have gotten them both kicked out of Goldman Sachs by peals of laughter and a personal escort from building security.

Mnuchin said the tax cuts – designed ostensibly to reduce the deficit – would not blow up the deficit because, quite simply: “This will pay for itself with growth and with reduction of different deductions and closing loopholes.”

This kind of magical thinking used to be confined to academic kooks who became presidential advisers. Now, in Trump’s first 100 days, former titans of finance are spouting the voodoo notion that reducing revenue leads to higher revenue.

They are also pretending like their boss has revealed as much about his finances as they have in their own process of job vetting and Senate confirmation. When asked when Trump would release his tax returns, alongside maybe a few more details about his tax plans, Mnuchin said bluntly: “The president has no intention. The president has released plenty of information and I think has given more financial disclosure than anybody else.”

Which brings us to credibility and ethics: the area where Trump has broken new ground in his first 100 days. This has been a truly incredible – and unethical – presidency to date.

Never mind the promises to stop the revolving door between the White House and lobbying, or to ban foreign lobbyists inside the White House or raising money for US elections. After all, Trump’s first national security adviser, Mike Flynn, was a paid lobbyist for Turkey and took Russian money.

No, Trump’s real achievement is that his self-enrichment is now just a normal fact of life. He never divested from his family businesses, and he never drew a line between his children’s personal and political affairs. He is in daily breach of the emoluments prohibition in the constitution, as well as the lease of his own Washington hotel from his own government.

He and his daughter have secured dozens of new trademarks for their own businesses, not least from China, which Trump no longer wants to designate as a currency manipulator, despite his many campaign promises. The state department’s website has promoted Trump’s Mar-a-Lago club, and the president’s adviser promoted Ivanka’s clothing brand.

And of course we know nothing about how Russian money has, or hasn’t, propped up Trump’s finances because we can’t and won’t see Trump’s tax returns. All we have are Trump’s flat-out denials of Russian financial support.

There was a time, not so long ago, when the media was obsessed with such transgressions. If a public official so much as broke the regulations on record-keeping, it was serious enough to feature in every press interview. But that was about Hillary Clinton’s email server, so it was totally different.

When her husband was caught in an affair with an intern, there was almost no other news out of Washington for the best part of 18 months. But those were the good old days, when perjury about sex was the highest of presidential crimes and misdemeanors.

So congratulations on your first 100 days, Mr President! You have scared the bejesus out of your allies and dumbed down the nation’s capital to a level previously reserved for tabloid trash. Your interviews are as nonsensical as your tweets. No other president has come close to your record, and all future presidents will clear the bar you have set. For that alone, you are exceptional.