President Trump. (Kevin Lamarque/Reuters)
Contributing columnist

Ronald A. Klain, a Post contributing columnist, served as a senior White House aide to Presidents Barack Obama and Bill Clinton and was a senior adviser to Hillary Clinton’s 2016 campaign.

The 100-day milestone for a presidency is overblown: In what other endeavor is so much emphasis placed on the score just 7 percent of the way into a contest? What does actually matter at this early stage in Donald Trump’s presidency is which of the flashpoints from this action-packed start will recede in significance as the rest of his presidency unfolds — and which events from the first 100 days are of enduring consequence?

At the outset, as a harsh critic of the president, I must acknowledge that for some constituencies, Trump’s first 100 days have been a success. For those who backed him to wrestle a Supreme Court vacancy from the Democrats, he delivered the most conservative nominee in a quarter-century. For those who want to reverse the increasing diversity of our country, Trump put out an unmistakable “not welcome here” sign. For those who craved fiercer firepower in the Middle East, Trump rained Tomahawks on Syria and the “mother of all bombs” on Afghanistan.

However, these hardcore Trumpers are not an electoral majority. So it is through the lens of other voters that the lasting impact of Trump’s first 100 days should be considered. This includes those who were dubious about him but who nonetheless took a chance on him to create jobs, “drain the swamp” and get results — and those who didn’t vote for him but were willing to give him a chance. From that perspective, three gigantic failures of the early Trump presidency will haunt the rest of his tenure.

First, as the candidate least beholden to a major political party to win the White House in decades, Trump chose — surprisingly — to eschew bipartisanship and tightly align himself with partisan Republican leaders. He ran a campaign opposed to both parties’ establishments. On primary nights, he devoted large chunks of victory speeches to describing how he would bring together Democrats and Republicans to hammer out compromise job-creating plans. Immediately after the election, a caravan of Democrats was invited to Trump Tower. And during the transition, some Democrats, even liberals, sent out feelers on infrastructure spending.

But in his first 100 days, Trump has governed as a hard-baked partisan. Unlike George W. Bush or Barack Obama, Trump did not choose any elected official from the opposing party for his Cabinet. He openly belittled Senate Minority Leader Charles E. Schumer (D-N.Y.) and fired racial epithets at Sen. Elizabeth Warren (D-Mass.). Bipartisan infrastructure spending was delayed in favor of a direct assault on Obamacare. While Trump has displayed a penchant for golf , the only member of Congress invited to play with him has been conservative Sen. Rand Paul (R-Ky.). He offered negotiations to Republicans on health care, but only threats to Democrats.

Second, Trump badly erred by putting fights about immigration, health care and cultural issues on the front burner — while neglecting and betraying the economic populist message that propelled his victory. True, he began his transition with a high-profile announcement about jobs at Carrier, and recently issued a largely hortatory “Buy American” executive order, but otherwise he’s largely been AWOL from (or affirmatively hostile to) his own campaign’s economic agenda since taking office.

Candidate Trump promised to declare China a currency manipulator on Day One — and then President Trump balked. He said he’d stick it to Wall Street — but hired more Goldman Sachs executives than any president in history. Candidate Trump said that he would “fight to pass” within the first 100 days a cornucopia of economic legislation: the End Offshoring Act, middle-class tax reform, affordable child care and elder care, a $1 trillion infrastructure plan, an educational opportunity act. Not one of these bills has been put forward, let alone fought for, and certainly not passed. No president meets all of his ambitious promises for action in the first 100 days — but no president has done less to even try to deliver on his economic promises than Trump.

Third, Trump has been stunningly blasé about staffing his administration. His victory was a surprise, so his transition was understandably less prepared. Republicans may be less easily enticed than Democrats into taking government jobs. But no president has done so little to staff so much of the government so far into his term as Trump.

This failure presents a long-term problem for Trump. Delays in filling higher-level jobs mean delays in filling mid-level jobs, and so on. Luckily for Trump, his administration has not had to face a major crisis. That string will break at some point. A hurricane will devastate a city, an offshore oil well will explode, an epidemic will threaten our shores. And a government without appointees in key posts will be woefully ill-equipped to cope. The inevitably inadequate response will have a lasting impact, not least for Trump.

Anyone who has underestimated Trump has learned a painful lesson. So the fate of his presidency is far from sealed. But in his first 100 days, the new president has dug a deep hole from which he will have to extricate himself in the next 1,361.