How do we fix it? Trump is like a toxic toadstool that grew from a putrid pile of ****. We've disposed of the toadstool, yet the pile remains, so how do we address it?
We have to face the real problem of our own greed and selfishness causing us to vote for known liars, cheats, and criminals just to get what we want. Or, we don't vote at all because we're doing OK and we just don't give a crap about anyone else. Our politicians are corrupt because we're corrupt. We put them there, and we keep them there.
Nearly everyone that voted for Trump did so based on their own paychecks. Or on their own stock portfolios. Or on some single ideological issue like abortion, or racism, or sexism, or personal freedom; that's important to them. All those votes based on "me". Not based on what's good for the whole country, or on helping all of us achieve a better life. Trump is the mascot for greed, and ignorance, and selfishness, and we have become a very greedy, ignorant, selfish culture. It's that simple. And unless and until we're willing to face up to this, we're going to continue to destroy each other and ourselves trying to get everything our own way at everyone else's expense.
And it's not just us, it's happening in nations all across the world.