"This is just one of the things that's at stake in this election," Harris added.
President Joe Biden also spoke about the shooting, demanding that Republicans in Congress "finally say 'enough is enough' and work with Democrats to pass commonsense gun safety legislation."
"We must ban assault weapons and high-capacity magazines once again, require safe storage of firearms, enact universal background checks, and end immunity for gun manufacturers," said Biden. "These measures will not bring those who were tragically killed today back, but it will help prevent more tragic gun violence from ripping more families apart."
The Biden-Harris administration has taken some action to prevent gun violence, including closing a loophole that had allowed firearms dealers to sell guns without running background checks on purchasers. Gun violence prevention advocates applauded the passage of the Bipartisan Safer Communities Act in 2022, but denounced Congress for not coming to an agreement on legislation that would require background checks for all gun purchases and ban assault weapons. The legislation banned gun sales to people convicted of domestic violence and funded state "red flag" programs to remove guns from people deemed a threat to themselves or others.
Republican presidential nominee Donald Trump has vowed to appoint federal judges who oppose limits on firearm ownership and has called himself "the best friend gun owners have ever had in the White House."
Both Harris and Biden expressed concern for schoolchildren across the country who are coming of age in a country where mass shootings make national news several times per year and where lockdown drills are routine at school.
"Our kids are sitting in a classroom where they should be fulfilling their God-given potential, and some part of their big beautiful brain is concerned about a shooter busting through the door of their classroom," said Harris.
The gun violence prevention group Giffords shared an account from Apalachee High School senior Sergio Caldera, who was in his chemistry class when he heard gunshots and someone pounding on the classroom door.
"They prepare you for these things," Isabella Albes Cardenas, an 11th grade student at Apalachee High School, told The New York Times. "But in the moment, I started crying."
The student-led group Students Demand Action said that "back to school season should not come with the fear of being shot."
"We deserve to go to school and focus on our education, NOT fear for our lives," said the group. "We don't have to live and die like this. WE DEMAND ACTION."