what did the Klan do so wrong exactly?

those lynchings? that was just a few bad apples, you wouldn't judge the entire black community for the actions of a few criminals would you?

They introduced Cocaine and illegal alcoholic beverages into a drug-free America. The war on drugs has escalated as a result. The constitution has been raped. You say that you are all for a ethical protection of our national constitution but the 18th Amendment still bleeds from your unholy desecration. How you have fallen from heavenly grace, morning star, son of the dawn!

You also have become weak, as we are; you have become like us.
All your pomp has been brought down to the grave,
along with the noise of your harps;
maggots are spread out beneath you
and worms cover you.
You said in your heart,
“I will ascend to the heavens;
I will raise my throne
above the stars of God;
I will sit enthroned on the mount of assembly,
on the utmost heights of Mount Zaphon.[b]
I will ascend above the tops of the clouds;
I will make myself like the Most High.”
But you are brought down to the realm of the dead,
to the depths of the pit of 4chan.
Those who see you stare at you,
they ponder your fate:
“Is this the man who shook the earth
and made kingdoms tremble?
The man who made the world a wilderness,
who overthrew its cities
and would not let his captives go home?”
All the kings of the nations lie in a welfare state,
each in his own pathetic tomb.
But you are cast out of your tomb
like a rejected conservative branch;
you are covered with the slain,
with those pierced by the blade,
those who descend to the stones of the pit.
Like a corpse trampled underfoot,
you will not join them in burial,
for you have destroyed your land
and killed your people.

Let the offspring of the wicked
never be mentioned again.
Prepare a place to slaughter his children
for the sins of their ancestors;
they are not to rise to inherit the land
and cover the earth with their cities.

“I will rise up against them,”
 declares the Lord Almighty.
"I will wipe out Babylon’s name and survivors,
her offspring and descendants,”
declares the Lord.
“I will turn her into a place for OWLS and into swampland;
I will sweep her with the broom of destruction,”
declares the Lord Almighty. [OH REALLY?]