Some Chronicle readers no doubt have noticed that we have not made an endorsement in the Republican or Democratic presidential primaries. It’s not an oversight, and it’s certainly not for lack of interest in two of the more intriguing primaries in recent American history.

In each case, there are compelling reasons we are not making a recommendation.

As a practical matter, the Republican primary has been settled, and an endorsement in the California primary would have no effect on the outcome. Donald Trump has secured the delegates necessary to claim the GOP nomination in Cleveland, whether party leaders like it or not — and many do not.

Neither do we.

Our editorial board has made plain its distaste for Trump’s low-substance, high-insult candidacy on numerous occasions. His campaign has been reckless, coarse and oozing with overtures to racial, national, class and religious resentments — and has continued even after he secured the Republican Party nomination. He instantly signaled that juvenile nicknames and irrelevant references to a spouse’s philandering would be on the table in the general election.

Clinton keeps her distance

Trump would not be in consideration for our endorsement if one of the Republicans with a modicum of qualification, dignity and serious purpose — think John Kasich, Jeb Bush, Marco Rubio — was still in contention.

Yet the case against a Trump presidency is so overwhelming that he is untenable even against an empty field.

As our March 3 editorial put it, the “threat from Trump’s ascension is the contempt he is spreading for the American values of pluralism, democracy and adherence to the rule of law.” He has consistently demonstrated either a stunning disregard or ignorance of history and the facts.

He has aggressively tried to inflame and exploit latent passions against minority groups, the judiciary, the media and global diplomacy.

Trump is, quite simply, a nonstarter.

The Democratic primary is a more complicated matter.

A decision to endorse, one way or the other, would be imperative if Hillary Clinton had less than a formidable lead going into California. Perhaps she would have followed through on the promise she made in February to debate Sen. Bernie Sanders in the Golden State in May. Perhaps she would have seen fit to meet in person with California editorial boards — including ours — to take questions in an extensive session.

Instead, Clinton’s California appearances have been limited to rallies, photo opportunities, perfunctory interviews and fundraisers, fundraisers and more fundraisers. Her double-cross on the debate pledge only feeds into the perception (established through the years) of the Clintons’ sense of entitlement and their presumption that they can set their own rules.

The nation’s most populous state deserves better.

It has received more, much more, from Sanders. The senator from Vermont has expressed his eagerness to debate at every turn. He came to our editorial board with no preconditions and took on pointed questions, and the interview was streamed live and archived on The Chronicle’s Facebook page.

Without question, Sanders, unlike Clinton, had great motivation to take risks. His chances of winning the nomination are roughly equivalent to a poker player trying to draw an inside straight.

Sanders’ break with political reality

Still, Sanders has had a profound impact on the debate, moved Clinton to the left, and, admirably, inspired young people to engage in politics. The 74-year-old senator has tapped the legitimate anxieties of generations who see the promise of opportunity that has defined this nation slipping away.

Yet there is a certain disconnection with reality in Sanders’ aggressively progressive promises. It’s simply not credible to think that a Republican Congress that frustrated President Obama at every turn will show any more deference to a self-described democratic socialist who wants to establish a government health care system and government-paid tuition at public universities. His pedestrian record of accomplishment as a senator does not suggest the skills to deliver a dauntingly difficult agenda.

Besides, the national debt already stands at $18 trillion, or about $60,000 for every man, woman and child in the America. While Sanders’ commitment to action on climate change as an economic imperative and moral obligation to future generations is worthy of admiration, it would be nice to see a candidate appealing to young people to express an equally unflinching dedication to addressing the debt burden we are leaving them.

As tempting as it would be to endorse Clinton as a candidate who blends idealism with practicality on domestic and foreign affairs — buttressed with a thick resume as first lady, U.S. senator and secretary of state — there remain serious questions about her judgment and ethics. Our editorial board would have liked to have pressed her on some of those issues, including myriad questions about her email server and those six-figure speeches to Goldman Sachs.

There was no shortage of California-focused issues that she could have addressed more fully in a California debate or editorial board sessions, including the federal role in water policy (she’s been a bit more detailed than Sanders), her retreat from support of the Trans-Pacific Partnership and striking the right balance between security and privacy rights (huge for the technology industry).

California loses from having a settled Republican nomination and a Democratic front-runner who has all but declared victory. Our editorial board will push for a reassessment of the primary calendar in 2020 that will assure that major-party candidates must do more than go through the motions to earn votes — and endorsements — in this state.