Philip M. Nichols is a professor of Legal Studies & Business Ethics at The Wharton School at the University of Pennsylvania. The opinions expressed in this commentary are his own.

When Howard Schultz ran Starbucks, he sent an unrelentingly positive message about the impact he hoped the coffee company would have on the broader community. But when asked during a CNN town hall whether he would divest his shares of Starbucks if he ran for president, Schultz had no clear message at all. While Schultz seems to have navigated the tricky waters of corporate dominance and social responsibility, it does not seem likely that as candidate — and then president — he could avoid the conflict between what is good for this country and what is good for Starbucks. To truly do so, he needs to commit to selling all his shares in the company.

Schultz vaguely promised during the town hall not to put himself in a position in which conflict exists. But his wealth is almost entirely in the form of shares of Starbucks; he owns more than 30 million shares and has options on 5 million more . Policy issues that affect Starbucks will affect Schultz's wealth, and most policy issues will affect Starbucks. Policies on infrastructure will affect how Starbucks' suppliers and customers reach their stores. Policies on minimum wages, internet commerce and immigration will all affect Starbucks. Starbucks wants to open a new store in China every 15 hours — foreign relations definitely affects Starbucks.

Schultz did claim in the town hall meeting that setting up a blind trust would remove any conflict of interest. His claim cannot be true. A "blind" trust would be blind in name only; almost all of Schultz's wealth is in the form of Starbucks shares, and putting those shares in a trust will not blind Schultz to that fact. And studies show that awareness of conflicting interests bias the way that people make decisions.

Even if, through superhuman effort, Schultz were to will himself into a state of mind that was not conflicted, he could not remove the appearance of conflict. Every time a President Schultz, or even candidate Schultz, meets with Chinese President Xi or French President Macron, or the leader of almost any country in the world, newspapers will run articles citing the number of Starbucks already slinging coffee in that country and asking what the leaders drank at their meeting. Trust in leaders and institutions is already shockingly low in this country, and the appearance of a conflict will only drive trust further down.

Businesspersons, in particular, would have reason to question decisions that might affect Starbucks' competitors or even other industries. The president often makes decisions that balance the interests of one industry against another. Ordering the release of oil reserves might, for example, help industries that consume oil but take a bit of profit from oil producers. If President Schultz were to issue an order that, hypothetically benefitted sellers of tea but hurt soft drink producers, would he be acting to promote the health of Americans or the health of Starbucks?

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