The biggest threat to the U.S. isn't another country or a known terrorist group. According to the Department of Homeland Security, "the most persistent and lethal threat" to the nation are U.S.-based White supremacists. Released Tuesday, the department's "Homeland Threat Assessment" reveals in the past two years, White supremacy extremists have been responsible for more lethal attacks in the U.S. than any other violent extremist group. "I am concerned about any form of violent extremism," Acting Secretary of Homeland Security Chad F. Wolf writes. "However, I am particularly concerned about white supremacist violent extremists who have been exceptionally lethal in their abhorrent, targeted attacks in recent years." According to the report, violent extremists have been responsible for "a significant uptick in violence against law enforcement and government symbols in 2020." It goes on to say White supremacist extremists have "consistently remained prominent among domestic extremist groups."