U.S. President Joe Biden warned Sunday at an Independence Day celebration event that COVID-19 has yet to be "vanquished," even if Americans have made huge progress against the pandemic.

"We've gained the upper hand against this virus," he told a large, cheering crowd of guests on the White House lawn. But he added, "Don't get me wrong: COVID-19 has not been vanquished. We all know powerful variants have emerged, like the Delta variant."

This year's Independence Day holiday, following 600,000 U.S. deaths from COVID-19 and amid a rise in the more aggressive Delta variant, is an occasion when Biden intended to highlight the achievement of his administration's pandemic response.

Biden, who has made fighting the coronavirus a key priority of his administration, had previously announced July 4 as a target date for Americans to gather in small groups for holiday and signal a return to greater normalcy in the middle of the pandemic.

Biden had also set a goal to ensure 70 percent of adults get at least one shot of the COVID-19 vaccine by July 4. But the country has fallen short of the target – 172 million Americans, or about 67 percent of the adult population, had received at least one dose, the U.S. Centers for Disease Control and Prevention said Friday. 

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On July 4th, American independence needs an honest reckoning

The total number of confirmed COVID-19 cases in the United States has surpassed 33.7 million, more than any other country in the world. As of Sunday, the seven-day average of new daily cases in the U.S. was 13,196, an 11 percent increase over the last week, according to data released by Johns Hopkins University. 

Public health officials are eying swaths of rural America where hospitals are starting to fill up again, especially in Utah, Missouri, Arkansas and Wyoming. 

In his speech, Biden struck an overwhelmingly optimistic tone and urged Americans to get vaccinated and defeat the virus. 

"This year the Fourth of July is a day of special celebration for we are emerging from the darkness of ... a year of pandemic and isolation, a year of pain, fear and heartbreaking loss," he told the crowd of around 1,000 people, including military families and workers involved in the COVID-19 response. 

He mourned the people who died, praised Americans who aided in the country's emergency response and said vaccines were the best defense against new variants of the virus. 

"It's the most patriotic thing you can do," he said of getting vaccinated. 

Anthony Fauci, America's top infectious disease expert, told NBC unvaccinated people now account for 99.2 percent of COVID-19 deaths.

Biden suggested that under his leadership, the country – bitterly and at times violently divided during the Donald Trump presidency – was "coming back together." "Over the last year, we have lived through some of our darkest days," Biden said. "We are about to see our brightest future."

He drew a comparison between the declaration of independence from the British Empire in 1776 and today's rapid recovery from the coronavirus. "Two hundred and forty-five years ago, we declared our independence from a distant king. Today, we are closer than ever to declaring our independence from a deadly virus," he said.

After the speech, the president and guests watch a 17-minute fireworks display set off from both sides of the Lincoln Memorial Reflecting Pool.

With the fireworks smoke barely cleared, Biden will have to return to a complex political fight for the survival of his legislative agenda this summer. Negotiations continue on a bipartisan infrastructure deal, and fractious debate within his Democratic Party looms on a much broader spending package that has no support from Republicans.   

(With input from AFP, Reuters)

(Cover: U.S. President Joe Biden delivers remarks at the White House at a celebration of the Independence Day in Washington, U.S., July 4, 2021. /Reuters)