Ten years have passed since a shooter at Sandy Hook Elementary School in Connecticut killed 20 children and six school employees.

US President Joe Biden said the tragedy compelled everyone to reevaluate their "fundamental principles and if this can be a democracy that protects the most innocent" in a written statement designating Wednesday, the anniversary, as a day of remembering.

In the wake of the massacre, many demanded tighter gun restrictions. However, the death toll from school shootings keeps climbing as debates over gun control continue ten years on, with nothing don on the ground. 

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Since Sandy Hook, there have been 189 school shootings in the US each of which has resulted in at least one fatality, according to research maintained by the independent K-12 School Shooting Database research group. 

Seventeen were "active shooter situations" - defined as "when the shooter killed and/or wounded victims, either targeted or random, within the school campus during a continuous episode of violence."

Despite making up a minor part of all shooting episodes, those incidents result in more than a third of all fatalities. In total, 279 died from being killed on school property during, before, or after school hours, including weekends.

A memorial for the victims of Sandy Hook was opened in November to the public, not far from the school grounds. Victims' names were carved into a wall that circled a sycamore tree.

Ban on semi-automatic rifles

Congress passed laws extending background checks and strengthening procedures to keep firearms out of the hands of potentially dangerous persons after 19 children and two teachers were shot dead at Robb Elementary School in Uvalde, Texas, in May of this year.

But despite the country seeing mass shooting after mass shooting, Congress has repeatedly failed to reauthorize a stronger measure outlawing assault guns that expired in 2004. Republicans' objection, which invokes the right to bear arms under the Constitution, is a major cause of this slowness.

Ten years on, President Joe Biden has renewed a promise to pass a ban on semi-automatic rifles.

He signed a landmark gun bill into law in June, but it fell short of reinstating the so-called assault-weapons ban that had been in effect before 2004. The effectiveness of this and other proposed gun control measures in preventing school shootings is still up for dispute, with arguments on both sides being made.

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Biden admits to failure

Biden said on Wednesday that America should feel "guilt" collectively for its failure to address gun violence. "We have a moral obligation to pass and enforce laws that can prevent these things from happening again," Biden said in a statement.

"I am determined to ban assault weapons and high-capacity magazines like those used at Sandy Hook," he said.

The massacre in Newtown, Connecticut, left 20 children and six adults dead in a five-minute shooting spree by a young man named Adam Lanza, who was armed with an AR-15 military-style assault rifle. Lanza later killed himself.

The shooting shocked America and the world, sparked heightened security measures at schools, and renewed a contentious fight for gun control laws that continues a decade later.