This week, pipe bombs were sent to prominent Democrats including George Soros, Hillary Clinton and Barack Obama. CNN also received one in the mail. Sadly, none of this was really that shocking. The news had an air of inevitability, being the culmination of what has been a hideously violent time in our political culture. Poison is coursing through the US body politic. Violence permeates political dialogue and sometimes erupts at political events.

The shocking thing is that some of the violence has been endorsed by the president himself.

At a rally last week in Missoula, Montana, President Trump celebrated the Republican representative Greg Gianforte, who violently attacked the Guardian reporter Ben Jacobs last year. Jacobs, who was simply trying to ask a question about healthcare, was body-slammed and hurt by Gianforte, who won election to the House but later pleaded guilty to misdemeanor assault. At the rally last Thursday, Trump cheered the congressman as a “tough cookie”, and roused his supporters by loudly proclaiming: “Any guy that can do a body slam, he’s my kind of guy.”

Trump has repeatedly invited his supporters to beat up protesters at his rallies, implying that the protesters bring this on themselves by disrupting him.

Neither the fatal shootings at a newspaper in Maryland nor the killing of journalist Jamal Khashoggi in the Saudi consulate in Istanbul have discouraged the president from blasting journalists as “enemies of the people”. At a CNN forum on Monday, Maggie Haberman of the New York Times talked about her children sobbing because they are so scared for her and their own safety because of the vitriol and threats that are flung at reporters covering Trump rallies. Arthur Gregg Sulzberger, the Times’s publisher, took on the admirable task of warning Trump during a White House meeting that his verbal savaging of journalists would, inevitably, lead to something terrible happening. But the president has not heeded him.

After tragedies, Trump talks from both sides of his mouth. Belatedly, he condemned the death of Khashoggi but then praised Saudi Arabia, which is widely believed to have planned and executed his killing, as “a great ally”. After the death of a protester in Charlottesville, where violent, torch-carrying mobs went on a wilding to defend Confederate statues, the president notoriously said “both sides” deserved blame for the violence, an outrageous statement he has repeated since.

Play Video 1:50 Potential explosives sent to Trump critics – video report

On Tuesday, Slate published an incisive piece condemning the president after a Monday night rally in Houston where he declared himself a nationalist. The headline on the article said it all: “Trump celebrates violence and nationalism at his rallies. Republicans are not pushing back.”

That was the same day the first pipe bomb arrived at the suburban New York address of philanthropist and major Democratic donor George Soros. Then, on Wednesday, came the sickening news that more suspected pipe bombs were sent to Democrats, to the homes of the Clintons and the Obamas. CNN was also a target, with a suspect package addressed to former CIA director, John Brennan, an Obama administration veteran and frequent Trump critic, who happens to appear mainly on MSNBC. Former Democratic party chairman Debbie Wasserman Schultz may have been the intended recipient for another bomb addressed to Florida. New York mayor Bill De Blasio has rightly called the pipe bombs an “act of terror”.

With FBI investigations just starting, it’s impossible to say whether the perpetrator or perpetrators were rightwing nationalists, but their intended victims suggest the possibility of such markings.

Sarah Sanders did issue a proper White House statement condemning the attempted bombings. “We condemn the attempted violent attacks recently made against President Obama, President Clinton, Secretary Clinton, and other public figures. These terrorizing acts are despicable, and anyone responsible will be held accountable to the fullest extent of the law. The United States Secret Service and other law enforcement agencies are investigating and will take all appropriate actions to protect anyone threatened by these cowards.” Obviously, the president’s aides want to avoid reflexive connections being made between the president’s increasingly irresponsible and violent rhetoric and the pipe bombs.

And yet, on the same day that CNN was the recipient of a bomb, the president took another shot at the press. At a Wisconsin rally, he said: “The media also has a responsibly to set a civil tone and to stop the endless hostility and constant negative and oftentimes false attacks and stories.”

Donald Trump attacks media 'hostility' after attempted pipe bombings Read more

The horrifying political violence that has been building for years and has been directed at Republicans, too, including when Republican representative Steve Scalise of Louisiana was shot and gravely wounded at a congressional baseball game in 2017. But in recent weeks, it has erupted with frightening regularity. On 14 October, in New York City, a violent scuffle resulting in arrests broke out after an appearance at a Republican club by Gavin McInnes, the rightwing founder of the Proud Boys, a group of self-described “western chauvinists” that the Southern Poverty Law Center has labeled a hate group.

The most eloquent reaction to the pipe bombs came from George Soros’s son, Alexander, who wrote an op-ed titled “The hate that is consuming us”, in the New York Times published on Wednesday. It began: “Bombs sent to my father, George Soros, and to former president Obama and Hillary Clinton are a result of our politics of demonizing opponents.”

The younger Soros noted that the vitriol used to be confined to the fringe extremes. “But something changed in 2016.” Since Trump’s election, it’s been spreading like a wild contagion. Rather than stoking the hate, the president needs to recognize the terrible recklessness of his own rhetoric.