Why not? Because his crude remarks undoubtedly played well with his "deplorable" base and because it has become so common for Trump to say crazy, offensive things about which no one gets as worked up as they would if the same words had come from a "normal" politician.
Indeed, Trump's headline-grabbing insults against Africa and Haiti had the accidental benefit of distracting attention from all his other "holy shit!" moments last week.
I'm not even thinking here of the revelation that Trump allegedly paid US$130,000 to a porn starlet who goes by the name Stormy Daniels before the election to keep her quiet about the extramarital relationship they allegedly had.
Ordinarily, being blackmailed by a porn actress would be a career-ender for any politician, but for this president it's barely a blip.
Expectations for Trump - a man who publicly boasted, in a presidential debate, about the size of his penis, notified one of his wives via a tabloid headline that he was divorcing her, and took part in professional wrestling shows - are so low that it's almost impossible for him to do anything that would be considered beneath him.
His spokespeople can always claim that voters knew what they were getting, and they would be largely right.
Even so, it's worth noting all of the stories last week that would have been big, big news in any other presidency and that are all but ignored in this one.
Let's start with the F-52 - the nonexistent airplane that Trump claims the United States is selling to Norway.
This is typical of Trump's invincible ignorance, which was on even greater display in the gobsmacking interview he granted the Wall Street Journal on January 11.
The Journal reporters asked Trump whether he was at all "concerned that delaying military exercises on the Korean Peninsula for the Olympics sends the wrong message to the North Koreans, that you're in some way bending to them?" Trump's reply: "You're the first one that's asked that question."
Really? You mean the President suspended military exercises - a reasonable decision - without even considering the possibility that this might encourage more aggression from Kim Jong Un?
If Trump's aides did not raise this possibility with him, they are guilty of gross negligence. More likely they did raise it - possibly in a briefing paper that the President didn't read - but it simply didn't register with a president who spends so much of his time golfing and channel-surfing.
More ignorance was on display when Trump insisted to the Journal reporters, "There's a big difference between DACA and Dreamers, OK? Dreamers are different."
No, they're not. Deferred Action for Childhood Arrivals (DACA) was a programme President Barack Obama created to protect from deportation people who had been brought illegally to the US as children.
They are also known as "Dreamers" because of a failed bill called the Development, Relief, and Education for Minors (Dream) Act, which attempted to grant these undocumented immigrants a pathway to legal residency.
By insisting on a non-existent distinction, Trump is once again revealing that he doesn't know what he's talking about when it comes to the basics of legislation.
Trump cloaks his ignorance and insecurity with pathological boasting.
In the Journal interview, he claimed, "I was always the best athlete, people don't know that." (They probably don't know that because it's not true.)
And, when asked whether Kim Jong Un is trying to drive a wedge between him and South Korean President Moon Jae In, he replied, "I know more about wedges than any human being that's ever lived."
Who knows what this self-appointed "wedgologist" is talking about? We've become used to having a president so incomprehensible that he makes the famously inarticulate George Bush snr sound like Winston Churchill by comparison.
This was not even Trump's only nonsensical boast in this very interview.
In the course of bragging that he has a superhuman ability to turn just about anyone into "my best friend," Trump said that "I probably have a very good relationship with Kim Jong Un of North Korea." Uh, sure. Who can doubt that "Little Rocket Man" and the "dotard" are pals?
On Monday, Trump tried to insist that he had had been misquoted because he'd really said "I'd have a good relationship with Kim Jong Un." The Journal released its recording of the conversation and stuck by its account even though it is hard to tell exactly what the President said.
Trump's protestations would be more convincing if he didn't lie quite so often. Last week he reached a milestone of mendacity - in the course of 355 days he uttered, according to the Washington Post, 2000 false or misleading statements. That's an average of 5.6 lies a day.
Not slowing down, Trump kept right on going, adding this whopper in the middle of the night on January 11: "Reason I cancelled my trip to London is that I am not a big fan of the Obama Administration having sold perhaps the best located and finest embassy in London for 'peanuts,' only to build a new one in an off location for 1.2 billion dollars. Bad deal. Wanted me to cut ribbon-NO!"
In reality, Trump cancelled his visit to London because he would not be welcome after repeatedly offending America's closet ally.
Almost everything else about that tweet is also false: The decision to sell the old US Embassy was made by President George W. Bush, not Obama, and it was done for security reasons. The new embassy, built at a cost of US$1 billion, not US$1.2 billion, has been described by Trump's own ambassador to the Court of St James's as a "bargain" that was paid for by the sale of other US properties in London.
Such self-serving lies may be dismissed by Trump supporters as relatively harmless - but in fact there is a big price to be paid for having a president whom no one can trust.
It makes it almost impossible, for example, to convince other countries to go along with the United States in any international crisis where the facts are in dispute.
Trump's blizzard of bullshit can also have a more immediate cost.
Witness the mass confusion that ensued after a Trump tweet sent at 7.33am on January 1: "'House votes on controversial FISA ACT today.' This is the act that may have been used, with the help of the discredited and phony Dossier, to so badly surveil and abuse the Trump Campaign by the previous administration and others?"
Actually, Trump's own Justice Department has admitted there was no evidence that the Obama Administration wiretapped Trump or his campaign.
By sending out this tweet, Trump undercut his own Administration's position in favour of renewing Section 702 of the Foreign Intelligence Surveillance Act, which authorises warrantless surveillance of non-Americans and is a vital tool for fighting terrorism.
Administration officials and congressional leaders panicked on seeing this witless tweet, which threw the impending House vote into doubt, forcing Trump to backtrack with a subsequent tweet.
Trump made no attempt, however, to undo the damage done by his other hyperbolic comments designed to discredit the investigation of his campaign's ties to Russia.
In his Journal interview, Trump continued to vilify former FBI Director James Comey, saying he has "proven to be a liar and a leaker," when Comey's reputation for probity is a good deal greater than Trump's.
He accused Comey of saving Hillary Clinton's "life," when, if anything, Comey's statement just 11 days before the election that he was reopening the investigation into Clinton's private email server helped to kill her campaign.
Trump also falsely claimed that "everybody hated Comey" and that "the FBI was in turmoil," when internal surveys showed that FBI agents supported Comey.
And he repeated his claim, based on nothing more than innuendo, that it was the Democrats, not him, who were guilty of collusion with Russia.
Trump took these false and troubling attacks to another level by accusing two FBI officials who had worked on the special counsel's investigation of "treason" for daring to criticise him, along with other public figures, in their private texts.
"See, that's treason right there," he said.
No, it's not - unless treason is redefined to mean, as it does in places like Turkey and Russia, any criticism of the supreme leader.
Normally it would be "yuge" news for a president to launch a McCarthyite assault on supposed traitors at the FBI.
But in Trump's case, we barely notice, because there is only so much outrage to go around.
That, in a nutshell, is the entirely inadvertent "genius" of Trump's presidency: His offensive and inane statements distract attention from his gaffes, lies, scandals, ignorance, self-sabotage, egomania, and even his attempted obstruction of justice.
- Foreign Policy
