Joe Biden condemned President Trump for holding a big event on the Fourth of July as the 2020 Democratic front-runner seeks to regain his footing in Iowa after a shaky debate performance.

He delivered a speech Thursday afternoon that began with a focus on "the incredible promise of the American future" and a history lesson that touched on Presidents John Quincy Adams, Abraham Lincoln, and John F. Kennedy before it quickly morphed into a tear against the current occupant of the White House.

"Three different presidents, of three vastly different eras, united by their faith in the power of the idea that is America. Constant in their dedication to the pursuit of humankind’s highest ideal — liberty," Biden said at an event in Marshalltown, Iowa. "What, I wonder, will Donald Trump say this evening when he speaks to the nation at an event designed more to stroke his ego than celebrate American ideals?

"Will he speak to the example America must set to inspire the world? Will he offer a robust defense of the democratic values that have always been our strength in times of crisis?" the former vice president added in prepared remarks.

President Trump speaks during an Independence Day celebration in front of the Lincoln Memorial. (AP Photo/Susan Walsh, Pool)

"We all know the answer to that. Donald Trump is incapable of celebrating what makes America great — because he doesn’t get it," Biden said. "He cannot distinguish between our Allies and our adversaries — because he does not grasp that America is the 'march of the mind' toward greater openness, greater understanding, greater human freedom to pursue lives of meaning and fulfillment."

Nearly 1,000 miles away, Trump marked Independence Day with a "Salute to America" event in front of the Lincoln Memorial that featured a speech, music, flyovers, and tanks. After facing criticism for issues ranging from cost to the politicization of the July 4 holiday, Trump delivered a speech that was devoid of politics and focused in large part on unity and paying tribute to the American armed forces.

“The future belongs to the brave, the strong, the proud, and the free. We are one people, chasing one dream and one magnificent destiny. We all share the same heroes, the same home, the same heart, and we are all made by the same almighty God,” Trump said.

Biden is visiting Iowa for the first time after he declared his third presidential run in late April. Still atop the polls in a wide Democratic field, the 76-year-old's lead took a hit after a crushing debate performance by Kamala Harris, who attacked his handling of racial issues in the 1970s.

In his afternoon speech, Biden hammered home the message that Trump cannot be allowed another four years in office and highlighted his Republican opponent's "embrace of dictators and strongmen," naming Russian President Vladimir Putin in Russia, North Korean leader Kim Jong Un, and Saudi Crown Prince Mohammed bin Salman.

Such relationships are "a fundamental rejection of everything our founders wrote into their Declaration," Biden said.

Earlier in the day, Biden walked in an Independence Day parade in Independence, Iowa, and spoke to a crowd of about 200 people in Waterloo. After being introduced by Rev. Frantz Whitfield, once a spiritual adviser to the Obama White House, Biden pitched himself as a pragmatic moderate and highlighted his relationship with former President Barack Obama.

Former vice president and Democratic presidential candidate Joe Biden walks in the Independence Fourth of July parade in Independence, Iowa. (AP Photo/Charlie Neibergall)

“Obama and I became close friends. Our families became close friends," Biden said. "My number two granddaughter is with his eldest daughter out in California right now hanging out at a friend’s house.” This was a reference to his granddaughter Maisy, 18, who attended the elite Sidwell Friends high school in Washington D.C. with Obama's younger daughter Sasha.

Biden wrapped up the day by attending a minor league baseball game in Des Moines. The Iowa Cubs game was preceded with a naturalization ceremony for roughly two dozen people, which was followed by a pre-taped message from Trump.

Biden clapped after the video played.

.@JoeBiden listened to a video of @realDonaldTrump following the naturalization ceremony in Des Moines tonight. pic.twitter.com/uOhPim6eBE — Paige Godden (@PaigeGodden) July 5, 2019

Biden also tweeted a video of himself congratulating the "newly minted U.S. citizens" and took a thinly veiled shot at Trump, whose hard-line position on immigration and border security remains a major rallying point for Democrats.

I had the opportunity to congratulate some newly minted U.S. citizens in Des Moines, Iowa. Tonight’s naturalization ceremony — on the anniversary of our independence — serves as a reminder that being a nation of immigrants is one of our greatest strengths. #FourthOfJuly pic.twitter.com/YbxD36sPRm — Joe Biden (@JoeBiden) July 5, 2019

"Tonight’s naturalization ceremony — on the anniversary of our independence — serves as a reminder that being a nation of immigrants is one of our greatest strengths," Biden said.

Biden was joined at the game by wife Jill and ran into Beto O'Rourke, a former Texas congressman who is also seeking the Democratic nomination.