Lol. Yes, it's because he's half white and white people can't be trusted to run a country: see Hitler, Every Bush, Clinton etc.
The problem exists right there, and it doesn't have anything to do with ethnicity.
It has to do with "run a country."
In America, we don't have a setup where anybody runs a country. What we have is the appearance of somebody running a country, because the people are dumb enough to think that government is running the country, and is supposed to run the country.
If the people realized the authority that they had in America, they might step up and shut the government down while keeping the Constitution and the Bill of Rights.
https://www.youtube.com/watch?v=H6b70TUbdfs