WHAT'S more volatile than President Donald Trump? The answer may be a lame duck Donald Trump after the United States midterm elections. The 80-year-old billionaire faces a bruising final two years in the White House if Republicans lose control of Congress in the Nov 3 polls amid voter anger over the Iran war and soaring prices. Investigations and a possible third impeachment would loom as his Democratic foes seek revenge. The president who loves to boast of his power would find much of it stymied.

But Trump with his back to the wall could cause major upheaval, from revenge at home to wars abroad — and influencing the race to be his successor in 2028. "I don't think he is going to go out with a whimper, he's going to try to go out with a bang," said Allan Lichtman, a professor at American University and author of Great American Presidents: The Twelve Who Transformed the Nation. "He can't stand not being the centre of attention. So this may spark him to be even more aggressive."