A concept so important, it is among the first words of the U.S. Constitution, the defense of our borders is as essential today as it was more than 200 years ago. In response to the breakdown of that function on September 11, 2001, the administration sponsored the USA PATRIOT Act, and created the Office of Homeland Security. Critics of those actions claim these measures give too much power to the government and impermissibly impinge on civil liberties; supporters claim they are necessary for national security.From the 1798 Alien and Sedition Acts to the present, the government has aggressively discharged its duty to ensure domestic tranquility, including jailing dissidents and forcing Japanese American citizens into internment camps. In this book, a leading legal scholar explains in detail the present federal actions and places them in historical context.