The Philadelphia protest is something of a flagship demonstration amid nationwide actions as Trump holds a controversial military parade in Washington, D.C.

"No Kings" marches in all 50 states were reminiscent of some of America's biggest debates, from Vietnam to civil rights.

Tight security ensured a family-oriented atmosphere at the U.S. Army's 250th anniversary parade despite liberal opposition and protests nearby.

The "No Kings" protest is taking place in cities across the country in response to Trump's military parade in Washington, D.C.