In the 10 years since the 1995 Oklahoma City bombing killed 168 people, roughly 60 right-wing terrorist plots have been uncovered in the United States, according to an upcoming report by the Southern Poverty Law Center's Intelligence Project. The plots, all foiled by law enforcement, reportedly included violent plans by antigovernment militia groups, racist skinhead organizations, and Ku Klux Klan members to use various types of chemical bombs and other weapons . . .
April 10, 2003: The FBI raided the home of William Krar, of Noonday, Texas, and discovered an arsenal of more than 500,000 rounds of ammunition, 65 pipe bombs and remote control briefcase bombs, and almost 2 pounds of sodium cyanide, enough to make a bomb that could kill everyone in a large building. Krar, reportedly associated with white supremacist groups, was sentenced to 11 years in prison for possession of a chemical weapon.
from US News and World Report
Read Bruce Schneier's piece on domestic terrorism and an Orcinus article on domestic terrorism for more information and a lively discussion.
If you meant international terror, then the answer is: a "shoot-to-kill" policy means we're going to shoot innocent people, and back it up with the same reasons as the terrorists. (Also from Bruce Schneier)