The event is expected to include about 6,600 soldiers, 50 helicopters and 60-ton M1 Abrams battle tanks, as well as possibly 200,000 attendees and heightened security to match.

Thousands of people have gathered in cities across the US to join protests against President Donald Trump, hours ahead of his military parade in Washington DC.

A coalition of pro-democracy, labor and liberal activists is arranging a full day of counterprogramming to make the case that Trump is hijacking the Army celebration to venerate himself.