There's no comparison.
The impeachment proceedings underway against our crooked president are totally unlike the last three cases in American history.
Johnson, Nixon, and Clinton didn't threaten the very core of our democracy by extorting another country to get dirt on a political rival, endangering our national security.
They didn't make the entire country question facts, or truth. They didn't bend reality into an alternate realty where Americans were forced to choice between the two.
Nixon's indictment of abuse of power doesn't even come close to the abuse Trump's done in three years... by openly defying the Constitution. Trump believes he's above the law.
Not one of the infamous three threatened the country's security like Trump has. Caught lying, Nixon resigned rather than drag Americans into a messy impeachment when he knew he was guilty and going to be convicted.
If convicted by the senate (it seems unlikely right now) Trump most likely won't accept the results, leading to a Constitutional crisis that not even the founding father's anticipated.
There's good reason to worry.
Democracy and the rule of law are at stake. We're facing an historical event that could very well be decided by partisanship, instead of facts and evidence.
Trump's base is gathering around the edge of a cliff, ready to jump off, if he asks. Like Jim Jones, Trump has followers who are ready to do his bidding without any regard to reality.
When the trial goes to the senate we're going to find out if there is any regard for the Constitution and the powers it conveys.
Will the GOP senators vote for a corrupt president?
Or, is there a chance that those gutless minions will reach that place of conviction, based upon the overwhelming evidence?
There's always the possibility that if the polls keep climbing to impeach and kick Trump out of office, his supporters could turn on him like rabid dogs who have been mistreated!
There's no other way to put it; facts and truth are on trial.
Related: Pelosi talks impeachment timeline with Stephen Colbert
Time for me to walk on down the road...