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 TrumpHouse Democrat slams Donald Trump Jr. for ‘serious case of amnesia’ after testimony Skier Lindsey Vonn: I don’t want to represent Trump at Olympics Poll: 4 in 10 Republicans think senior Trump advisers had improper dealings with Russia 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 ClintonGrassley blasts Democrats over unwillingness to probe Clinton GOP lawmakers cite new allegations of political bias in FBI Top intel Dem: Trump Jr. refused to answer questions about Trump Tower discussions with father 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.