The recent [July 13] attempt to assassinate Donald Trump was shocking. The former president and Republican presidential candidate was struck in the ear [and inches from certain death] when a gunman [Thomas Matthew Crooks] fired shots at a rally in Butler, Pennsylvania. One person in the audience [Corey Comperatore] was killed and two people [David “Jake” Dutch and James Copenhaver] were seriously wounded.

But we can’t really say the shooting was surprising. We ought not to fool ourselves: We live in a violent time when people quite often try to achieve their objectives through force. Politics reflects the wider society, and we’ve seen a disturbing rise in shootings in schools, workplaces, and other locations. We need to recognize that these acts will keep happening.

I don’t believe Americans are more violent than other people, but there are elements of our history and culture that align with violence. We celebrate the mythology of America’s settlement and western expansion, when force was used to drive Native Americans from their land. Today, our country is awash in guns, making it easy for disputes to escalate. Gun dealers have exploited political distrust to drive sales, including sales of deadly AR-style rifles like the one used against Trump [and the other victims]. By many estimates, there are more guns than people in the U.S.

Shootings are so common they can leave us feeling numb. As Jay Caspian Kang writes in the New Yorker about the Trump shooting, “A loner with an AR-15 commits an act of violence, and we typically have nothing to say except that this seems to happen all the time in America.”

Of course, political violence is not new. Four of our presidents — Abraham Lincoln, James Garfield, William McKinley, and John F. Kennedy — were assassinated. Kennedy’s death stunned me personally. His 1960 campaign and election were among the factors that inspired me to get involved in politics.

Political violence seemed to peak in 1968, when Martin Luther King, Jr. and Robert F. Kennedy were assassinated within a two-month period. Like the current time, it was an era of passionate divisions in American society.

Franklin Roosevelt, Harry Truman, Gerald Ford and Ronald Reagan survived assassination attempts while in office. Reagan was shot and, fortunately, recovered quickly, but his press secretary, James Brady, suffered life-altering injuries. Two members of Congress, Gabrielle Giffords and Steve Scalise, were seriously injured by would-be assassins in the past few years.

Meanwhile, distrust of government has grown dramatically. Sixty years ago, when I was first elected to Congress, I was impressed by the civility I encountered from Republican and Democratic colleagues and from most constituents. I recall only one truly threatening incident. I was riding in a convertible in a parade in a small town in Indiana when a man came running toward me. I don’t believe he had a gun, but I remember seeing a knife. A sheriff’s deputy was riding in the car behind me; he stepped in and saved me, I’m sure, from an attack.

Today, public officials (and even volunteer election workers) often receive hateful messages on social media, sometimes escalating to death threats. This undermines our democracy and puts a real burden on law enforcement to determine which threats to take seriously.

President Joe Biden, speaking after the Trump rally shooting, said we all should “lower the temperature” of political rhetoric. That’s essential, but it only goes so far.

We have to accept that we’re living in dangerous times. We need to be sure our security forces are well equipped and properly trained. Lapses, like the failure to stop the gunman who fired at Trump, need to be investigated and remedied. When crowds gather, at rallies, parades, and elsewhere, authorities will have to be on the lookout.

One thing we know about violence is that it generates more violence, and that’s especially true of political violence. We need to do all we can to prevent it.           

Lee Hamilton, 93, is a senior advisor for the Indiana University (IU) Center on Representative Government, distinguished scholar at the IU Hamilton Lugar School of Global and International Studies, and professor of practice at the IU O’Neill School of Public and Environmental Affairs. Hamilton, a Democrat, was a member of the U.S. House of Representatives for 34 years (1965-1999), representing a district in south-central Indiana.