For over one hundred and fifty years, the Ku Klux Klan has been terrorizing citizens of the United States of America through threats to commit violence along with actual violence. They've infiltrated government and law enforcement, and terrorized innocent people.
They've murdered more American citizens than al Qaeda, ISIS or similar Islamic extremists have. And they've inspired other acts of terror throughout the United States.
There is no difference between their modus operandi and al Qaeda's, and are a larger threat to the homeland than any Islamic extremists. Like other terrorist organizations, their members should be arrested and their assets seized.