Federal authorities can continue to wiretap and conduct surveillance on non-Americans within the United States according to the Foreign Intelligence Surveillance Act (FISA) recently reauthorized by the U.S. Senate and earlier by the House. Senate majority leader Harry Reid said the measure was imperfect but necessary to “protect us from evil in this world.” Sen. Dianne Feinstein claimed that FISA had led to 100 arrests from 2009-1012 and said that “No one should think the targets are U.S. persons,” but critics of the measure aren’t so sure.

When the government targets Americans for surveillance it must secure a warrant from a special 11-judge court of U.S. district judges appointed by the Supreme Court. With foreigners the surveillance court approves annual certifications but the possibility remains that Americans could be caught up in so-called “back door” searches attached to foreign subjects. Sen. Ron Wyden, an Oregon Democrat, sought to know how many Americans had been the subject of surveillance but was unable to obtain the information. Like the ACLU, he believes FISA threatens Americans’ civil liberties. That leaves the question of what governments do with the information they have.

Lawrence Wright’s The Looming Tower confirms that government security agencies possessed crucial information about the 9/11 plotters but withheld it from other government agencies. That helped a terrorist group operating out of a cave in Afghanistan to topple the World Trade Center and kill thousands. Government investigators knew that Major Nidal Hasan, an Army psychiatrist, was an acknowledged jihadist but took no action against him. Hasan’s 13 murders at Fort Hood, Texas, in 2009 exceeded the death toll from the first terrorist bombing of the World Trade Center in 1993.

So even with its Intelligence Community network of 17 agencies, government has a hard time protecting us from “evil in this world,” as Harry Reid put. What of Dianne Feinstein’s claim that FISA will not target “U.S. persons”? Americans have grounds for not believing anything until it has been officially denied. Feinstein is also leading the charge against assault weapons but packed a gun herself when under attack by the New World Liberation Front during the 1970s.