Scout posted a decent Reason.com article about why this is a bit premature on FaceBook the other day. Even if you don't like Trump, He IS the President, and the President gets a lot of leeway on how they handle things.
I think the fallout would be horrific for the Democrats and maybe even all Republicans,
I think you're correct. For better or worse, we elected him, and the Dems aren't fooling everyone. If they impeach, 60 or 70 million people are going to read that as "*expletive deleted*ck what you want, the government is ours, and there's nothing you can do about it." Questions like "What's the point in voting, the politicians will just put one of their own in?" will be asked. Certainly you'd see a pretty big voter backlash against any Republicans that helped. I think the Dems will be fine, because their voters will see it as vindication, and many would support the move.
I'd be very concerned with what the disenfranchised third or so of the country will decide their best bet is to do.
I also think you'd see a pretty fertile ground for power hungry racist/nationalist/actual fascist demagogues. Not to mention whatever the hell Mr. Trump might decide to do with the folks that would follow him. Would he even accept impeachment?