WASHINGTON, Feb. 14 (Xinhua) -- One year after a mass high school shooting that killed 17 students, there is no sweeping, federal-level U.S. gun legislation on the horizon, with experts saying the situation is unlikely to change.

On Feb. 14 last year, a gunman entered Marjory Stoneman Douglas High School in Parkland, Florida, and opened fire on campus with an assault-style rifle, killing 17 students and educators within six minutes of hell.

Over the past 12 years, a number of mass killings have grabbed headlines: in 2007, a student at Virginia Tech killed 32 people; in 2012, a deranged gunman entered the Sandy Hook elementary school and murdered 28 people, including many children; in 2016, a gunman killed 49 people at a nightclub in Orlando; and in 2017, a total of 58 people were killed and hundreds wounded in the Las Vegas mass shooting.

A recent PBS News Hour/Marist/NPR poll found a slim majority of 51 percent of Americans favor stricter firearms-related legislation, down significantly from the poll's finding nearly one year ago after the Parkland killings, when 71 percent of Americans favored tighter gun laws.

Republicans and Democrats are at odds over the issue, with Democrats calling for more gun legislation, and Republicans fearing that more laws might not lessen the violence, but could infringe on rights guaranteed in the U.S. Constitution.

"This situation probably will not change until Democrats have firm control of the House, Senate, and presidency," Brookings Institution Senior Fellow Darrell West told Xinhua. "It has been hard to pass bills due to Republican intransigence."

Breanna Deutsch, the communications' manager at the Institute for Constitutional Government of The Heritage Foundation, noted that conservatives have offered a number of evidence-based solutions "that we think narrowly target specific threats to public safety without broadly infringing on the constitutional rights of law-abiding citizens."

"Unfortunately, because many on the left are primarily concerned with imposing severe restrictions on all lawful gun ownership, there isn't the consensus needed to move forward with a specific legal framework," she told Xinhua.

The gun legislation conversation has become more robust in the year since the Parkland shooting, Deutsch said. Eight states have passed "red flag laws," which allow for the temporary but immediate disarmament of individuals who pose a danger to themselves or others.

Hundreds of firearm-related bills have been introduced at the state and federal level based on a variety of theories about how to keep Americans safe while respecting fundamental constitutional rights, Deutsch said.

According to the Giffords Law Center, lawmakers on both sides of the political divide in more than two-dozen states have enacted nearly 70 new gun laws, and the U.S. state of Washington voted to increase the legal age to purchase semi-automatic rifles to 21 from 18. But those are far from the sweeping federal gun laws that many gun control advocates favor.

"Whatever is going to take place on this issue is more likely to be on the state level than at the federal level, particularly with the divided Congress," Republican strategist and TV news personality Ford O'Connell told Xinhua. He added that Democrats in Congress may introduce bills, but they won't go far in a divided Congress.