Will this time be different? The telling moment will come in a few weeks, or the point in the past when public attention diverted, the horror of another mass shooting, in Las Vegas, or San Bernardino, or Orlando, or Newtown, fading into the pattern of ordinary lives. The sequence has repeated for decades.

There is something different since the ghastly events at Marjory Stoneman Douglas High School in Parkland, Fla., where a young man, armed with an AR-15, killed 17 people and injured more than a dozen others. The survivors, friends and family members, have made their voices heard. They have spoken in pain, with urgency and uncommon frankness about the need to address the country’s gun problem.

They don’t sound resigned, or helpless, or overwhelmed. They have voiced their impatience with the usual tired responses.

Most of all, they have sent the helpful message: Yes, something productive can be done. They have gotten the attention of some allies of the powerful gun lobby. President Trump, who has an opportunity to leverage his position as an outsider, has appeared supportive of raising the age for purchasing some guns. He has leaned toward banning “bump stocks,” which turn semiautomatic weapons into automatic weapons.

Both steps take the right direction.

Yet the president seems most keen on arming trained teachers, their presence, more than anything to serve as a deterrent. The reasoning goes: A gunman would be less likely to attack knowing teachers are armed and prepared. One of many flaws in this misguided proposal, long favored by the National Rifle Association, is that it misses the larger concern. Research shows that more guns lead to more gun violence and gun deaths.

The country doesn’t just have a school shooting problem. It has a broader problem with gun violence. Dealing with the challenge requires first acknowledging that sound policy-making must focus on reducing the more than 300 million guns in circulation across the country.

That is a big job. Yet progress can be made. An often-noted review of 130 studies in 10 countries, published in Epidemiological Reviews, concluded that new restrictions on gun ownership and purchasing often led to reductions in gun violence.

Australia may be the most famous story, cited by one of the young Parkland survivors at a White House meeting last week. He recalled that a mass killing by a man with a semiautomatic rifle resulted in a ban on automatic and semiautomatic rifles, a gun buyback program that yielded 650,000 guns. Australia now has a gun registry and a permit required for new gun purchases.

The gun homicide rate dropped roughly 40 percent with the restrictions. The rate of suicides by firearm decreased more sharply.

The idea isn’t to imitate precisely Australia. Americans must contend with the Second Amendment, the Supreme Court a decade ago abandoning the traditional interpretation related to a “well-regulated militia” for securing an individual right to bear arms. Yet it is worth reminding again: That court ruling left the way open to substantial regulation of guns.

So, not only does gun regulation reduce gun violence. The opportunity exists for taking steps without harming gun rights. That means seeking to strike an appropriate balance to advance public safety — through, say, strong background checks, bans on certain weapons and even buybacks more ambitious than the smaller versions held by cities. The way to make a difference is squeezing steadily the overload of guns.