"They came prepared to do what they did, as if they were on a mission." — San Bernardino (California) Police Chief Jarrod Burguan after at least two heavily armed attackers opened fire on a banquet at a social services center for the disabled, killing 14 people and seriously wounding more than a dozen.
"Do we work with our allies to degrade and destroy this threat and do we go after these terrorists in their heartlands, from where they are plotting to kill British people?" Or do we sit back and wait for them to attack us?" — Britain's Prime Minister David Cameron before lawmakers voted to join the international campaign of airstrikes against the Islamic State group in Syria.
"He was always plotting revenge against people he felt did him wrong and you know it didn't take much for him to feel like somebody did him wrong. So he would spend a lot of time trying to get back at people, trying to figure out ways to get back at people."— Barbara Mescher Micheau, ex-wife of Robert Lewis Dear, accused in the deadly shooting at a Colorado Planned Parenthood clinic.