2014 November - Republicans win a Senate majority in mid-term elections, gaining control of both houses of Congress and further reducing President Obama's room for man oeuvre.
2014 December - US and Cuba begin steps to normalize diplomatic relations after more than 50 years of stand-off.
2015 March - President Obama announces that 10,000 US troops will remain in Afghanistan as advisors and trainers until 2016.
2015 June - US accuses Chinese hackers of massive breach of personal data of nearly four million government workers. China denies any role.
2015 December - FBI say Muslim couple who shot dead 14 people and wounded 21 others at office party in San Bernadino, California, were Islamist extremists who had prepared the attack, the worst on US soil since September 2001, in advance.