Raleigh News & Observer via Getty Images. Trump on Tuesday in North Carolina

What exactly is Donald Trump trying to say?

Maybe Trump asked Russia to spy on Hillary Clinton last month. Possibly, he kind of implied Fox News host Megyn Kelly was menstruating when she asked him some tough questions last year. On Tuesday, he seemed to suggest that gun-rights activists assassinate Clinton if she won the presidency. Or, he was totally kidding! Or, as some of his spokespeople have suggested, we simply don’t understand what he means ― or he doesn’t mean what he seems to mean.

The only lucid message Trump’s sending at this point: He’s not a reliable communicator. It doesn’t matter if you have the best words ― as Trump has literally claimed ― or if you’re refreshingly frank and un-PC. If no one understands what the words mean, and you can’t even commit to their meaning, you’ve failed as a leader.

“If you want to be a successful leader, you must communicate without ambiguity at all times,” said Gautum Mukunda, a Harvard Business School professor who studies and writes about leadership. “It’s one of the first things we teach ― all ambiguous comments will always be interpreted in the most negative fashion.”

Trump’s casual, squishy rhetoric is at best a huge liability to his campaign and a source of confusion to voters. At worst, it’s a danger to the lives of others. Thomas Friedman, writing in The New York Times, compared Trump to right-wing Israeli politicians whose rhetoric led to the assassination of Yitzhak Rabin.

This is why chief executives typically stay relentlessly on message, Mukunda explained. They rarely joke ― and when they do, it’s not about a serious topic. So, at a mining company that has a culture committed to safety, no one ― including the CEO ― would make a joke about safety, he said. President Barack Obama likes to kid, but in an administration committed to stamping out sexual assault, he’s not going to josh about violence against women. He’ll stick to remarks about how many almonds he eats at night.

After months of making statements Trump later explains away as jokes or as comments misinterpreted by the media, it almost doesn’t matter whether he is sinister or thoughtless. Either way, if he were to actually win the White House, his loose manner of speech would become critically dangerous. A president, or any leader of a large organization, must speak with clarity.

“You’re not just responsible for what you say. You are responsible for what people hear,” retired Gen. Michael Hayden told CNN Tuesday. The former head of the CIA was reacting to 11 words (in bold below) that Trump uttered at a rally in North Carolina earlier that day.

“Hillary wants to abolish ― essentially abolish the Second Amendment,” Trump said. “By the way, if she gets to pick, if she gets to pick her judges, nothing you can do, folks. Although the Second Amendment people, maybe there is, I don’t know.”

Some heard this as an incitement to violence.

Trump later said it was merely a play to get Second Amendment-rights activists to vote ― although he had been talking about what happens if Clinton wins.

House Speaker Paul Ryan (R-Wis.) said Trump’s Second Amendment remark was a joke gone awry, but “you should never joke about something like that.”

This wasn’t the first time Trump has said something off the cuff, only to later claim he’d been misunderstood or was joking. There were comments during primary season about Fox News host Megyn Kelly having “blood coming out of her wherever.” More recently, there was a call to Russia to please expose Hillary Clinton’s emails.

In the Kelly case, Trump later said he was talking about her nose. No one heard it that way. In the Russia case, he said he was kidding.

There have been too many times when Trump or his supporters have said, “Oh he didn’t mean that,” Matt Latimer, who runs a communications firm in Alexandria, Virginia, that works for Republican and Democratic candidates, told HuffPost. “It’s become difficult to know what he actually does mean. That’s a problem if you want people to follow a message.”

This isn’t just a matter of a newbie politician going off-script, added Latimer, who was deputy speechwriter for President George W. Bush. Bush “did a lot of things off the cuff, but people knew where he stood and understood him.”

When regular people are talking, it’s natural for us to sort of meander and say things that maybe don’t quite reflect our meaning ― or even reveal too much about what we think.

“This salad is actually good,” my 5-year-old daughter said the other evening, exposing the fact that either she doesn’t like salad, or maybe doesn’t like salad I make. Who knows? It was unclear.

A president doesn’t have that leeway.

“As a human being that’s OK, but as president of the United States what you say has an impact and a candidate can have a detrimental impact,” Latimer said. He added that Trump should’ve learned by now that you can’t just wing it. As president, “Trump could be in the middle of an inaugural speech and make some off-the-cuff remark and then we’re at war with China.”

Of course, politicians often keep things vague. That may be because they don’t have a firm grasp of what they want to do, or they don’t want to promise anything in particular. Sen. Bernie Sanders (I-Vt) may want to break up big banks, but he’s not sure how, or doesn’t have a plan yet. Vice President Joe Biden wants to cure cancer.

Politicians might also be vague because maybe they’re not informed on an issue and don’t want to admit that.

But surely, the most awful explanation for Trump’s apparent lack of clarity is that it’s intentional. A speaker could be purposefully unclear because he wants plausible deniability when others accuse him of insinuating something terrible.

Like when Sara Palin, running for president in 2008, said Obama was “palling around with terrorists.”

Jeff Shesol, a former speechwriter for Bill Clinton who now runs a communications firm, told HuffPost this is the likely explanation for many of Trump’s comments ― including the latest remark about the Second Amendment. Trump has taken the mantle of Palin and carried it further than perhaps anyone else in American politics, he said.

“He is a master of the dark art of insinuation and the half-completed thought and usually his intent is pretty transparent,” Shesol said. “This is one of many areas where Trump is a dangerous anomaly.”