Domestically there was Anwar al-Awlaki who was a US citizen who proselytised against the USA. His 16 year old nephew who was also a citizen was killed as well, despite no known involvement.

To be fair, earlier in the year the administration promised to implement additional safeguards and oversight for these programmes, but brass tacks a progressive administration killed US citizens in non-war zones because of an executive decision with no due process.