Brand power doesn’t arise from what most of us marketing amateurs think. It isn’t based on lots of people knowing or liking a brand. It results instead from two features: a brand’s differentiation from other brands and its relevance to its intended public, as research by the Young & Rubicam ad agency established long ago. By those two criteria, Trump dominates utterly. He is completely unlike all other candidates, and he is far more relevant because he’s real – he talks naturally, not like a politician, and he says out loud what a segment of voters is thinking.

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He differentiated himself further on Wednesday, outlining a foreign policy like nothing any other candidate has enunciated or is likely to. He called for a major buildup of the military, though even a conservative Republican like former Wyoming Senator Alan Simpson has said it’s bloated and should be slimmed down. He threatened to withdraw from NATO unless other members pay more, though no U.S. president of either party has ever gone remotely near enforcing such a demand. He used the phrase “America first,” explicitly recalling the isolationist group by that name that, until Pearl Harbor, lobbied hard to keep the U.S. out of World War II.

Like Trump himself, many of the positions he described are way outside the mainstream. Will the speech build him as a leader by attracting more followers? Probably. His core supporters won’t mind that the speech was pre-written and that he read it from a teleprompter, a practice for which he has ridiculed other candidates; those supporters will figure he’s just doing what has to be done. And he will likely attract some undecided voters simply by giving a speech on an important topic with presidential trappings – backed by American flags, in Washington a few blocks from the White House – delivering a message that will strike many as at least plausible. With next Tuesday’s winner-take-all Indiana primary now looking crucial to Trump’s chances of going to the convention with a clear majority of delegates, attracting a few more undecided voters could make a big difference.

Trump’s main challenger in Indiana, Ted Cruz, on Wednesday made a very belated stab at serious differentiation, naming Carly Fiorina as his running mate. The move is a clear attempt to attract women voters, who Trump has alienated massively with derisive comments throughout his campaign. And maybe it will make a difference in Indiana, though a former Hewlett-Packard CEO who fired thousands may not seem highly relevant to the women voters Cruz is after.

The entire U.S. political class and everyone interested in leadership will draw many lessons from the 2016 presidential race. The importance of brand power, specifically of differentiation and relevance, may well be one of them.