The media focus these last 10 days has been all about President Trump’s reaching his first 100 days in office — and what, if anything, he’s accomplished during them.

Not much, seems a fair conclusion, despite the narcissist’s self-description of “the first 100 days of my administration [as] just about the most successful in our country’s history.” With an overall approval rating hovering around 40% — the lowest for any modern president at this point in his presidency — offset by a 96% rating amongst those who voted for him, it’s clear that if he’s accomplished anything, it’s to more sharply divide an already very divided country. 

But it’s not the achievements, or lack thereof, of his first 100 days that are the real issue, it’s the fact that he’s got another 1,350 days to go: a lot of time for a lot more mischief.

If Trump has distinguished himself for anything over the past three months, it’s for flip-flopping on key international issues. No, it turns out, China is not “a currency manipulator.’’ And NATO: it’s not “obsolete’’ after all. At least, it seems, his White House staff can occasionally bring him back to reality.

Arguably, one could view these reversals as a welcome sign of maturity: when he is exposed to the big picture, as it were, he’s not embarrassed to backtrack on his campaign rhetoric. But his behavior as he celebrated his 100 days instead highlighted — once again — his immaturity and lack of judgment.

On Saturday, the 100-day anniversary, Trump opted for a campaign-style speech in Harrisburg, Pennsylvania, instead of attending the White House Correspondents Dinner. The last president to miss the bipartisan Washington event was Ronald Reagan a few weeks after he was shot.

Trump’s middle-finger rebuff to the dinner was obviously aimed at bucking up support from his base. The Washington Post’s Michael Gerson, a conservative columnist, described Trump’s Harrisburg speech as “the most hate-filled presidential communication in modern history … the kind of speech George Wallace would gladly have given as president.”

What, one wonders, does Trump hope to gain by narrowing his already limited appeal even further? With his historically disastrous approval rating, Trump needs to reach out to, not slap down, those who voted against him.

Then, in a scattering of interviews over the weekend, clearly designed to hype his 100-day achievements, he came across as not so much divisive as weirdly erratic: “I stand by nothing,’’ he proclaimed in response to one journalist’s question.

Talking to another journalist, he referred to North Korea’s Kim Jung-un, the youthful despot running perhaps the most vicious dictatorship in the world, as a “pretty smart cookie,’’ whom Trump would be “honored’’ to meet with. It’s one thing to be purposely diplomatic about the head of a country whose nuclear arsenal could eventually pose a threat to the US mainland; it’s beyond bizarre, however, to make out-of-the-blue comments that portray him as a respectable international figure.

And while it’s certainly not in the same league as back-slapping Kim, inviting Rodrigo Duterte, the murderous Filipino strongman, to the US caused consternation even amongst Trump’s White House consiglieri.

Reviewing the president’s off-the-wall behavior a few days ago, Joe Scarborough, co-host of MSNBC’s “Morning Joe’’ and before that a Republican Congressman, opened the discussion with the following disclaimer, “I’m not saying Donald Trump has dementia, but …”

In fact, whether Trump has some serious mental deficiency was exactly what Scarborough was suggesting. Meanwhile, presidential historian Douglas Brinkley described Trump’s behavior as “surreal disarray,’’ before pinpointing it as “a confused mental state.’’

And the Washington Post’s very conservative columnist, Jennifer Rubin, offered a provocative no-win choice in her op-ed piece on Monday: “Is Trump nuts, ill-informed, or a liar — or all three?” After discussing various psychiatrists’ public opinions about Trump, she argued that in the 2020 elections, voters “may well conclude that he’s too erratic, self-absorbed, dishonest, confused, and ignorant to be president. They won’t need a doctor to tell them that.’’

I suppose the suggestion from a right-wing journalist that he won’t get re-elected is good news, but we’ve still got 1,350 more days with the ignorant, confused, and erratic President Trump running the most powerful country in this increasingly chaotic world.

Trump likes to boast that his contradictory actions keep the opposition guessing. Maybe so, but it also reveals there is a thin line between confusing your enemies by how you behave and total irrational behavior.

Nor does his divisive campaign-style approach to the presidency make rational sense. With a decreasing minority supporting him, Trump’s refusal to reach out and broaden his base will only erode his already sputtering presidency.  

And assure that he’s a one-term, four-year — at most — oddity. Be thankful, as they say, for small favors.