John O. Brennan — American Public Servant born on September 22, 1955,

John Owen Brennan is an American government official who is the Director of the Central Intelligence Agency. He has served as chief counterterrorism advisor to U.S. President Barack Obama; his title was Deputy National Security Advisor for Homeland Security and Counterterrorism, and Assistant to the President. His responsibilities included overseeing plans to protect the country from terrorism and respond to natural disasters, and he met with the President daily. Previously, he advised President Obama on foreign policy and intelligence issues during the 2008 presidential campaign and transition. Brennan withdrew his name from consideration for Director of the Central Intelligence Agency in the first Obama administration over concerns about his support for the use of waterboarding by the CIA under President George W. Bush. Instead, Brennan was appointed Deputy National Security Advisor, a position which did not require Senate confirmation... (wikipedia)

The CIA has acknowledged that it has detained about 100 terrorists since 9/11, and about a third of them have been subjected to what the CIA refers to as 'enhanced interrogation tactics,' and only a small proportion of those have in fact been subjected to the most serious types of enhanced procedures.
Unfortunately, in war, there are casualties, including among the civilian population.
Jihad is holy struggle, a legitimate tenet of Islam, meaning to purify oneself or one's community.
The risk of just one terrorist with just one nuclear weapon is a risk we simply cannot afford to take.
To me, terrorists should not be able to hide behind their passports and their citizenship, and that includes U.S. citizens, whether they are overseas or whether they are here in the United States. What we need to do is to apply the appropriate tool and the appropriate response.