What happens when there’s a crisis?

When, not if, because that is the nature of the presidency: Bad things happen — often early on, sometimes anticipated, sometimes out of nowhere. Consider the historical roster: Somali pirates holding an American captain hostage (Barack Obama’s administration), the Chinese forcing down a Navy aircraft and detaining its crew (George W. Bush), a siege and raid gone bad at a cult complex in Waco, Tex. (Bill Clinton).

For a new president, April is the cruelest month; add John F. Kennedy’s Bay of Pigs fiasco to that litany of springtime woes. An unseasoned new president and a wobbly team still learning how to work the system and work together are going to be more susceptible to blunders than later on.

But a crisis under President Trump — a real crisis, not the seemingly endless series of self-inflicted wounds that has scarred the new administration — poses a far scarier situation than with the usual fledgling presidency. Trump’s unforced errors have implications and ripple effects for when the real problems inevitably arrive.

First, the best leaders become even more calm, deliberate and focused in moments of stress and emergency. Trump lashes out — before checking the facts, before considering the consequences. Some people believe Trump tweets strategically, as part of a plan to distract. Perhaps, but even so, his calculations have a propensity to boomerang.

That danger has never been more clear than with his irresponsible accusations of wiretapping by Obama. Trump isn’t playing chess — he’s playing checkers, with an elementary schooler’s urge to upend the board when the game isn’t going his way.

What happens when the president is provoked by a real problem, not an unsupported report by a loudmouth talk-radio host and a right-wing website? Twitter is a risky enough tool for making foreign policy, but the other tools at a president’s disposal are even riskier. Trump’s fury over everything from paltry inaugural crowd counts to falling poll numbers does not portend a trusty hand when the challenge comes, whether from China, Iran, North Korea, Russia or elsewhere.

Second, the skill set of steady presidential leadership must be augmented by a functioning team of principals, deputies and advisers. This truism envisions both the “functioning” part, as opposed to the evident rivalries and schisms inside the Trump administration, and the “team” part, as opposed to the virtual absence of key personnel. Who is available, in this home-alone administration, to ask the second- and third-order questions about the consequences of a particular course of action?

If anything, Trump has thrown additional sand in the gears of the existing institutional machinery. His continuing feud with the intelligence community erodes the rapport and trust essential for operating effectively during a crisis. His rocky start with key allies — those phone calls with the leaders of Australia and Mexico, and the takeaways by other foreign leaders — similarly augurs poorly for the kind of concerted action and united front essential in an international emergency.

Third, Trump’s predilection to assert and cling to untruths in the face of contrary evidence raises questions about his capacity to absorb and act on unwelcome information. If the president can’t accept that he lost the popular vote, what happens when advisers deliver bad news? More disturbing, Trump’s tenuous connection to the truth dangerously undermines his credibility with everyone from the U.S. public to foreign leaders.

The sobering state of affairs was underscored in a remarkable tweet Monday by the ranking Democrat on the House Intelligence Committee, Adam Schiff of California: “We must accept possibility that @POTUS does not know fact from fiction, right from wrong. That wild claims are not strategic, but worse.” Schiff is not a partisan hothead, so his discussion of the sitting president in language more suited to a commitment hearing was that much more striking.

“The implications are quite extraordinary,” Schiff said in a follow-up interview with NPR. In a crisis, he asked, “how much credibility will the president have left to persuade the country of what has happened, what needs to be done? How much credibility will he have with our allies to get them to back us up? So these have real-world repercussions. . . . It’s the president losing the credibility of the office.”

That’s the most alarming part of all. Because there is some hope, however scant, of a presidential learning curve. But trust once squandered is not easily, if ever, regained. And without it any president will remain severely hobbled.

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