How many Americans are targeted for assassination?

When The Washington Post's Dana Priest first revealed (in passing) back in January that the Obama administration had compiled a hit list of American citizens targeted for assassination, she wrote that "as of several months ago, the CIA list included three U.S. citizens."  In April, both the Post and the NYT confirmed that the administration had specifically authorized the assassination of Anwar al-Awlaki.  Today, The Washington Times' Eli Lake has an interview with Obama's top Terrorism...