Donald Trump was officially sworn in as the 45th president of the United States after a long and divisive campaign. Trump, seated in front of his wife Melania and children and directly next to former President Barack Obama, looked reserved throughout the inauguration ceremony. Both he and Vice President Mike Pence were sworn in by Supreme Court Justice Clarence Thomas. For more: http://abcnews.go.com/Politics/inside-donald-trumps-inauguration-day/story?id=44906987 For live updates: http://abcnews.go.com/Politics/live-updates-donald-trumps-inauguration-day/story?id=44895255 SUBSCRIBE to ABC NEWS: https://www.youtube.com/ABCNews/ Watch More on http://abcnews.go.com/ LIKE ABC News on FACEBOOK https://www.facebook.com/abcnews FOLLOW ABC News on TWITTER: https://twitter.com/abc GOOD MORNING AMERICA'S HOMEPAGE: https://gma.yahoo.com/