As a military parade rolls through Washington, DC, on Saturday – President Donald Trump’s birthday – millions of Americans are expected to protest in what organizers predict will be the strongest display of opposition to Trump’s administration since he took office in January.

Millions of Americans are likely to tune in, whether to show bipartisan support for the troops, for Trump or just out of curiosity.

While the idea might be novel for many Americans, military parades are common spectacles in many parts of the globe.