Exactly one year ago, two Islamic extremists, a couple married in the name of Allah, walked into a Christmas Party with the husband's fellow employees and began slaughtering what they considered non-believers.
Syed Farook and his Pakistani wife, Tashfeen Malik, were enraged by a mandatory training session and lunch celebration with holiday decorations including a Christmas tree which Farook was forced to attend.
Emails discovered by the FBI and police reveal that Malik objected to the Christmas setting and was upset her husband had to go.
Farook attended the party, and even posed with his victims just before leaving the building. He then returned with his wife killing 14 people and injuring 22 others with pistols and an assault rifles that a friend had bought for Farook.
Shortly after the attack, the couple posted an online message pledging their allegiance to the Islamic State and its leader, Abu Bakr al-Baghdadi.