A video showing rehearsals in Washington, D.C. for the upcoming military parade marking the 250th anniversary of the United States has triggered alarms on social media, with users comparing the footage to scenes from authoritarian regimes like the Nazis, the former Soviet Union, and present-day North Korea.
The event, which also coincides with President Donald Trump's birthday, has brought to the capital a total of 6,500 troops, 150 vehicles and 50 aircraft, which will parade around the National Mall.
