In a decent society, the role of government would be severely limited, so that the jerks who become politicians would have a reduced chance to achieve their goals.
I use the principal that I want the government so weak that even in the complete control of the worst people possible it can do little or no damage. This means it can’t do much when people I like are in power, but so be it. It’s why so many of use fervently fought the PATRIOT act and such- it’s not how the act can be used by a good president, it’s how much damage it can do in the hands of a bad one.