American counter-terrorism officials are increasingly, and rightly, concerned about Americans joining groups like Al Qaeda. According to a Congressional Research Service report, between Sept. 11, 2001, and May 2009, authorities made arrests in 21 jihadi-related terrorism plots involving people radicalized in the United States. Between May 2009 and November 2010 there were 22 such plots, resulting in two attacks, including the 2009 one at Ft. Hood, Texas. Considering the numbers, it is unsurprising and appropriate that Rep. Peter T.