Watergate: A scandal for the ages that could yet be eclipsed

Former US president Donald Trump instructed the crowd to march on the Capitol on January 6, 2021

Richard Nixon is pictured in August 1974 saying his goodbyes to White House staffers after resigning the US presidency over the Watergate scandal

Fifty years since it ignited Washington, the Watergate affair remains a cautionary tale on the threat of untrammeled presidential power and the yardstick against which all other political scandals are judged.

The accusations against Trump -- that he incited a deadly riot to disrupt the peaceful transfer of power as part of a conspiracy to overturn an election -- appear "far more serious," says history professor Michael Green.