While this topic has certainly got a lot of (libertarian) press over at Reason, what brought it to my mind was the so-called "Commander-in-Chief" debate hosted on CBS on November 11. During this debate, both Newt Gingrich and Mitt Romney were asked about whether they would assassinate Americans like Anwar al-Awlaki.
Since I don't watch news television, I don't know to what degree the media covered the Awlaki assassination. I imagine it was not covered very much, so I will redirect you to the above link to Reason Magazine and to the less partisan wikipedia page. If you are not interested in reading the gory details, I will summarize the story. Anwar al-Awlaki was a Yemeni-American who later became a popular imam and self-proclaimed anti-Western jihadist. To be clear, he was a citizen of the United States. He has been linked to many terrorist activities since then, including the "Underwear Bomber," the Times Square Bomber, and the Fort Hood Shooter. For a more complete list, see the wikipedia page. In any case, he was put on the Obama Administration's targeted assassination list in early 2010. Thus we used drone assaults to bomb the various places the administration thought they could kill him. In September 2011, the United States of America successfully killed him in Yemen. Two weeks later, we killed his 16 year old son, American citizen Abdul-Rahman al-Awlaki. [More below the fold.]