“I will be the greatest jobs president that God ever created,” Donald Trump recently said.

Why is Trump so confident? “I have relevant experience by creating jobs and assets,” he said. “I have created tens of thousands of jobs” and “an unbelievable company worth billions and billions of dollars.”

Even if Trump’s claims for his performance as a CEO are accurate, would this record imply that as the U.S. president, he would be able to serve the public interest by increasing American employment? Trump and his supporters believe it would. I do not.

Increasing a company’s U.S. workforce and increasing U.S. employment are different projects. Business plans that increase a company’s profits and workforce typically do so by taking sales away from the company’s American rivals. Such plans will not increase American employment.

Furthermore, CEOs and presidents need very different knowledge and skills to perform their respective tasks. To design business plans that increase a company’s profits and workforce, a CEO needs information about the company’s personnel, production and distribution processes, expansion options, and financial and tax positions.

To serve the public interest by increasing employment, a president must know how government expenditures and international-trade, interest-rate and tax policies would interact to affect not only employment but economic efficiency and the distribution of income more generally. These two knowledge-sets barely overlap. Business plans are not macroeconomic policy plans.

A CEO must be able to identify ideal trading partners and craft the most profitable deals that could be made with them, which will often be the deals that maximize the joint profits of the company and the trading partner. A CEO’s ability to identify ideal trading partners will usually be of no use to him as a president because the attributes of businesses that make them desirable partners are different from the attributes of foreign governments or members of Congress that make them valuable deal participants. Also, a president’s potential trading partners are well known.

The information that businessmen need to identify contract terms that maximize the profits a deal will yield their company and trading partners are also different from those a president needs to determine how any term in a deal would affect his own and his “trading partners” parochial political needs and the public interest as they respectively conceive it.

Since few of the deals that Trump mentions are U.S.-employment-increasing deals with foreign governments or Congress, his vaunted ability to design profit-and-workforce-increasing business deals is a poor predictor of his ability as president to craft desirable U.S.-employment-increasing deals with foreign governments and Congress.

There is also the opposition aspect. Although CEOs occasionally encounter effective opposition, they usually have plain sailing when it comes to getting their business plans adopted and implemented. Presidents typically face far more serious opposition and must exercise a wide range of skills to secure the adoption and implementation of their economic plans. Congress can refuse to pass the legislation the president proposes and can threaten to cut the budgets of administrative agencies that implement the president’s preferred policies; courts can misinterpret or misapply the president’s plan or declare it unconstitutional; and state and local officials may refuse to implement it.

A U.S. president must exercise many skills to secure the adoption and implementation of his or her economic program that a CEO need not have — among others, skills at making policy compromises, at granting potential opponents support for other legislative and administrative decisions they want, and at drumming up public support for his or her program. Trump has yet to show that he possesses these skills.

An individual’s success as an entrepreneur at increasing his company’s U.S. workforce and profits has little bearing on his likely success as the president of the United States. Trump’s apparent failure to recognize the difference between business plans and government macroeconomic policies and between a CEO’s and president’s knowledge and managerial-skill requirements should make us all doubt his ability to perform well as America’s president.