Nixon, Reagan, W - all were obviously terrible Presidents. The tremendous damage that each of them did to America cannot be overestimated.

Here's an example https://en.wikipedia.org/wiki/Reagan_administration_scandals - and many of these scandals were completely outrageous, like the CIA smuggling literally tons of cocaine to trade to give weapons to friggen terrorists! (And that one was proven in court...)

And neither Clinton nor Obama undid any of the damage. In fact, Clinton and Obama expanded the right wing policies of their Republican predecessors more often than not.

Obama's deep love of fossil fuels and military technology is particularly awful in hindsight.

But of course, Obama and Clinton seem like secular saints compared to the devil that is Trump.