I was having lunch a few days ago with an executive headhunter and a couple of colleagues, talking about the leadership issues at major companies, and as we left, one of them said, “We should congratulate ourselves—we just spent an hour-and-a-half without even mentioning Donald Trump.”

It does seem impossible for two or more U.S. adults to meet without talking about him, but in this case there was a larger issue. Our topic was leadership, and it hadn’t occurred to any of us to bring Trump into the discussion. Which raises a significant question: Is Trump a leader?

The sobering answer is yes, of course he is.

He has followers, millions of them. What’s more, it isn’t even surprising that he has attracted a giant following. He’s doing the four fundamental things that leaders do, as I’ve elaborated before and won’t repeat here. But while he’s doing what leaders do, he is not doing what winning presidential candidates do as they vie for the world’s most important leadership job.

In today’s Super Tuesday primaries and the winner-take-all primaries two weeks from today, Trump could virtually lock up the Republican nomination. If he does, he will have rewritten the rules of how to become a major party’s nominee. We’ll then discover if he can rewrite the rules of becoming president.

The fundamental rule of the past has required a candidate to walk the finest of lines: Show that you’re one with the people while simultaneously being presidential. That’s what Jeb Bush was trying to do, and we saw how far it got him. He talked authoritatively about the most important policy issues while wearing an open-necked shirt with the sleeves rolled up, mentioning his traditional family, speaking Spanish with Spanish-speakers, and generally finding ways to relate to every crowd he was with.

Trump is the opposite of all that. He arrives at campaign events in his personal chopper, mentions his Wharton education, doesn’t care who knows about his multiple marriages, and often wears a suit, French-cuffed shirts, and a tie. His policy positions are vague and apparently formed on the spot; rather than talk much about policy at rallies, he’s crude, immature, petty, and clownish. He’s the anti-candidate, and so far that has been his strength.

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If he is the Republican nominee and Hillary Clinton wins the Democratic nomination, as now seems most likely, the election will ask voters to choose between the two most disliked candidates since the relevant opinion polls have existed. Those polls suggest that Trump would lose massively. If that were to happen, it would at least confirm that the traditional path to the presidency hasn’t been completely obliterated, considering that Clinton is running a largely conventional campaign based on claims of competence.

But even if Trump wins the nomination and loses the general election, he will force all of us who are interested in leadership to focus on a reality we may sometimes forget: that leadership is not in itself noble or evil, but is a tool that can be used by anyone for any number of purposes.