Ex-GM CEO: I've always voted Republican until now
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Former chairman and CEO of General Motors Daniel Akerson says that worries about Donald TrumpDonald John TrumpReporters defend CNN's Acosta after White House says he 'disrespected' Trump with question Security costs of Trump visit to Scotland sparks outrage among Scottish citizens Ex-CIA officer: Prosecution of Russians indicted for DNC hack 'ain't ever going to happen' MORE will dictate how he votes this November.

“And I have always voted for Republicans for president. Not this year," Akerson wrote in an op-ed for The Washington Post on Wednesday.

"The compelling rationale behind this decision: leadership. A good leader must demonstrate such qualities as competence, integrity, empathy, character and temperament. Hillary ClintonHillary Diane Rodham ClintonDHS secretary: No sign Russia targeting midterm elections at 2016 level Twitter suspends Guccifer 2.0 and DCLeaks accounts after indictments Elon Musk donated nearly K to Republican PAC, filings show MORE has these essential qualities. Donald Trump does not," he added.

Akerson said that Trump's knowledge of foreign affairs and economics is "rudimentary” and his views "misguided."

"His threat to impose prohibitive tariffs on trade would repeat mistakes that contributed to the Great Depression. His words and actions have rattled our European and Asian allies at a time when Russia and China are resurgent. He has demonstrated neither the capacity nor the inclination to learn from experts in global economics," he wrote.

The former GM chief added that in every executive job he ever had, important decisions were made after "countless hours" of listening to experts, studying trends and learning from others. Trump, according to Akerson, does none of the above.

However, Clinton "has been tested" and "has demonstrated balance, calm and an even temperament,” he said.

Both Trump and Clinton have spent significant time on the campaign trail in Michigan, where GM remains a major employer. Last week, they both gave speeches on economic policy in the state.