Democratic presidential candidate Hillary Clinton. (Paul Sancya/Associated Press)

Hillary Clinton’s top priority, if she is elected president, shouldn’t be enacting an infrastructure plan or pushing immigration reform. It should be — must be, if she is to succeed on any substantive front — to combat her own worst instincts.

To be clear, I desperately want to see Clinton elected, not only because the alternative is Donald Trump and not only because it is time for a woman in the White House. Clinton has the experience, intelligence, skill and discipline to be an excellent president.

But she has also repeatedly displayed tendencies, overlapping and toxically reinforcing, that could undermine all those positive attributes:

To believe — correctly, in my view — that she is the victim of an implacable political opposition, and to respond by hunkering down and lashing out.

To believe — again, correctly — that she is being held to different, higher standards than others, and, rather than accepting this unpleasant reality and adjusting her behavior accordingly, to rail against it on the theory that nothing she does will ever satisfy the critics.

The Post’s Matt Zapotosky breaks down the unknowns following the FBI’s announcement on Oct. 28 that it will renew its Hillary Clinton email probe. (Bastien Inzaurralde/The Washington Post)

To believe that her own good works are so extensive, and her goodwill so evident, that questions about her behavior can stem only from the malicious intent of political enemies, or the ravenous appetites of a hostile media.

To respond to demands for information by elevating lawyerly caution over political judgment. To apologize if and only if circumstances require — and then not until the passage of time and the imperative of contrition have drained the moment of any sincerity. To bet that any potential problem will blow over, not fester, even if unhappy experience dictates the exact opposite.

Finally, to surround herself with a closed circle of advisers inclined more to enable than to prevent, and to reinforce Clinton’s us-against-the-world mentality rather than to challenge it.

These instincts were on display from the moment of Bill Clinton’s 1992 presidential campaign through the Clintons’ two terms in the White House. They reappeared during Hillary Clinton’s 2008 presidential campaign and again — with a vengeance — this time around.

If there is an episode that encapsulates most if not all of these instincts, it is, of course, her handling of those damn emails.

These self-destructive instincts were on display at the outset of the email mess. Clinton wanted to keep emails on one device; her staff complied and accommodated when it should have pushed back — hard.

Burned by the serial scandals and non-scandals of her husband’s administration, Clinton prioritized maintaining what she once mournfully described as a “zone of privacy” over ordinary rules regarding doing government business on government devices. Once again, that instinct for self-protection backfired. “I don’t want any risk of the personal being accessible,” she told aide Huma Abedin in one email.

These self-destructive instincts continued when the email issue first arose. Thinking like a lawyer advised by other lawyers, Clinton chose to delete emails that she deemed personal. She had the legal right to do so, and it wouldn’t have been a big deal, before she left office, to expunge personal emails written from a government account.

But the mass deletion of emails that Clinton’s team alone deemed personal, conducted after the State Department asked for its official archives back, was guaranteed to create a firestorm when it became public. As anyone who has spent as much time in Washington, under as much of a microscope as Clinton had, should have known it inevitably would.

“Why didn’t they get this stuff out like 18 months ago? So crazy,” exasperated former Clinton adviser Neera Tanden asked in an email when Clinton’s private server and mass deletion became public. “I guess I know the answer. They wanted to get away with it.”

After the email story broke, Clinton had to be pressured to choke out an apology. Tanden, again, nailed it: “Apologies are like her Achilles’ heel.” Once more, the details dribbled out, grudgingly and, as a result, inflicting even more damage.

Even before the unfortunate letter from FBI Director James B. Comey fanned the email flames, a President Clinton was certain to face incessant, multiple investigations from congressional Republicans seizing on what Rep. Jason Chaffetz (Utah) described as a “target-rich environment.”

All of this is unfortunate, outrageous — and unavoidable. If Clinton continues to be her own worst enemy, if she were to behave in office as she has too often before, she will make it all that much worse. She needs to guard against this by learning, finally, from the mistakes of the past.

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