Even Nixon wasn’t a total bad guy

There is no real standard for best and worst leaders, it all depends on your perspective. 
For those who despise Richard Nixon as a crooked leader, they probably do not appreciate his economic achievement in ending dollar convertibility to gold and creating the “petrol dollar” that paved the foundation for dollar supremacy in the coming decades. 
Those who underestimate Jimmy Carter as a weak leader probably do not appreciate his kinder side of refraining from entering into any war during his administration.
People who dislike Trump say he is cunning and unpredictable, but those who like him regard him as blunt and straightforward. For those working-class people who support Trump, he is the Moses they believe will lead them from poverty to prosperity. Trump promises to bring them jobs and raise their incomes. 
At the end of his presidency, if Trump can turn around the US economy he will likely be remembered by Americans as a good leader, despite all his bragging and sexual exploits that have provided regular jokes for late-night monologues. Time will tell.
Yingwai Suchaovanich