I have the same objection of many candidates. The desire for personal power drives a lot of people to seek the presidency in the first place. Hillary's at the top of my list because of her mix of desire for power and her ability to get it.
You can want power all day long and have crazy ideas but when it comes down to it, if you don't have the touch needed to actually seize it then you're ineffective. Do you honestly think a President would be allowed to seize mail?
Which is a more real danger to you, a crazy guy locked up in an asylum because he raves about wanting to kill everyone or a methodical, cautious serial killer? The guy in the asylum might want to kill more but the serial killer is the one to worry about.