Lynne Sladky/AP Photo

In the wake of one of the deadliest mass shootings in U.S. history, Vice President Joe Biden praised the victims of last week's movie theater massacre for inspiring the nation with their acts of courage and valor.

Speaking to a group of police officers in Manalapan, Fla., Biden somberly recalled the everyday heroes of the Aurora, Colo., shooting that left 12 dead and more than 50 injured - including the man who died while shielding his girlfriend from the attack, the Air Force reservist who dove to save his colleague's life and the others who sprung into action to help wounded victims during the shooting.

"These are the people who define who we are as a nation. They are the hymns of our hope," Biden said, at the National Association of Police Organizations' annual convention at the Ritz-Carlton Palm Beach.

"People stepped up. They make us proud of our country, and maybe more importantly at this moment, they make us confident that this country is made of that sterner stuff," he said.

Biden's talk was originally scheduled as a campaign event to discuss collective bargaining and security policy, but in light of Friday's shooting, he said, it "doesn't seem appropriate" to talk politics.

In 1994, then-Senator Biden championed the Violent Crime Control and Law Enforcement Act, which banned the manufacture of 19 semiautomatic assault weapons. The law, which enjoyed NAPO support, expired 10 years later - making it again legal to buy AR-15-style rifles, like the kind authorities believe alleged shooter James Holmes used in the theater attack.

During his talk, Biden did not mention Holmes, whose first court appearance came today.

Instead, he used his solemn 20-minute speech to honor shooting victims and thank police officers for their continuous bravery.

"There's no group of Americans who understand, who have internalized, who have had to deal with, every day of their life, the national tragedy that we're coping with now, more than all of you," he told a packed room of officers.

Get more pure politics at ABC News.com/Politics and a lighter take on the news at OTUSNews.com

Biden pointed to Aurora's police department for their brave work, touting that officers arrived on the scene of the shooting within 90 seconds. Some refused to wait for ambulances, he said, instead literally picking up victims and driving them to hospitals in their squad cars.

"In this moment of our grief, the entire nation is reminded of how grateful we are for what you do," Biden said. "Not withstanding all the political chatter we'll hear, I truly believe that the vast majority of the American people are as committed as I am to never letting you down."

The vice president also offered words of comfort for victims' families and loved ones.

"There will come a moment when the memory of your daughter, your son, your husband, will bring a smile to your lips before it brings a tear to your eyes," he said.

"My only prayer is that it will come sooner than later - but it will come."