Isn't the job of POTUS technically a government one? Well, if you have to take an exam to work for the USPS, shouldn't you for the top spot? Donald Trump did not know Puerto Rico was a commonwealth of the U.S.. Maybe if he was required to take a civics exam (which he probably would have failed), he would be precluded from running for the presidency. Therefore we may have been saluting an alternate #45 if Donald Trump had to take a test.
Why is this important?
One should be able to prove they have basic knowledge of the country they wish to lead.