On the National Mall, enclosed within almost 20 miles (32 kilometers) of high-security fencing, nearly 7,000 soldiers and about 150 military vehicles paraded to intermittent cheers.

Rain had threatened to wash out the event but it never came, much to the relief of those lining the four-lane street that runs past the White House, where Trump stood watching and frequently saluting the passing troops.

The crowd was mostly quiet as soldiers in uniforms dating back to the 1700s marched past, bar the occasional shouts of "Thank you, Army!" that spurred cheers and whoops.

Many wore Trump's signature red "Make America Great Again" baseball caps, but others attending made clear they supported the Army -- but opposed the norm-bending president.

"Personally, I'm not a fan of Trump, but I'm a fan of the Army," said Andrew Smith, 24, whose brother serves in the military.

"I feel like we can separate politics and what we stand for, and then hopefully get along," he added.

- 'Beat Fascism!' -

Marty Wrin echoed the sentiments expressed among the crowds of protesters gathered outside the parade area in Washington, and around the country Saturday.

"I'm proud to be American," insisted the 56-year-old IT worker from Washington, wearing a hat saying "resist" and holding a sign saying "Go Army. Beat Fascism!"

"I'm proud of our democracy, and I'm worried about our democracy right now for the first time in my life," he told AFP.

Wrin said he was impressed by the parade, but did not like something he associated with dictatorships happening on US streets.

"It's the Army being used by Trump to make himself feel more powerful," he said.

With cloudy skies overhead, people stood on tiptoes to catch a glimpse of the military gear on display.

Several children sat on their parents' shoulders to get a better view and waved back to soldiers sitting atop tanks and other armored vehicles.

Michele Sabat, who said she had attended several past Trump rallies, told AFP she was thrilled that she had traveled from Pennsylvania to watch the parade.

"I wanted to honor the military, I feel it's the right thing to do. They protect us, they save us, and you've got to respect them," the retired 68-year-old said.

She sat on a curb next to Camila Rodriguez, 30, watching as thousands of troops marched by in the largest such parade in decades.

Rodriguez, an auditor from Boston, said she was impressed by what she saw.

"All the troops... There's so many of them. So anything to support them," she said.

"I will always be here for that."