President Trump’s rhetorical style, under intense scrutiny amid the tragedies and threats of the past week, is nothing new.

From the opening moment of his presidential campaign in 2015, Mr. Trump has prided himself on his practice of stirring up hornet’s nests. The mockery, the winking calls to violence, the provocative policy moves, the incendiary language seen by critics as fear-mongering – these are not gaffes. They’re tools with an eye toward an end: winning.

On Tuesday came another such move – word of a planned executive order targeting “birthright citizenship.” The goal, Trump told Axios, is to end the practice of bestowing US citizenship on anyone born on US soil, regardless of whether their parents are citizens. The idea sparked an immediate uproar, and argument over the 14th Amendment, which has long been interpreted to offer wide citizenship rights.    

Many legal experts were skeptical of the idea’s chances in court. But the timing seems plain: One week before the midterm elections, Trump is fueling the divisive immigration debate, with an eye toward making sure his supporters turn out to vote.

For Trump’s purposes, this rhetorical style – both in tone and substance – is effective. Or at least, it can be interpreted as such. After all, he rode it all the way to the presidency.

When asked Monday night on Fox News if he should dial back his rhetoric, in the wake of Saturday’s mass shooting at a synagogue and the discovery of pipe bombs mailed to prominent Democrats, he pointed to his supporters’ reaction.

“You saw the group saying, ‘No, don’t tone it down, don’t tone it down,’ ” he told Fox host Laura Ingraham, referring to his rally Saturday in Murphysboro, Ill., hours after 11 Jewish worshipers were fatally gunned down in Pittsburgh.

Trump has long faced calls to “tone it down” – even, he says, from his own family. At a campaign rally in Boca Raton, Fla., in March 2016, on the eve of the Florida primary, he spoke of how his wife and daughter Ivanka wanted him to act more “presidential.”

“I sort of like the other way better,” he said playfully.

As a candidate, Trump’s message often was, “Elect me, and you’ll see just how presidential I can be.” But in office, he has largely ignored that demand, opting to remain in campaign mode. At a rally last March, he mimicked “presidential style” as over-the-top boring, before reverting to his usual combative persona.

“The idea of being provocative is obviously something that’s been part of his personal doctrine for a while,” says Republican pollster David Winston, a longtime adviser to the Republican leadership in the House and Senate.

But “the thing about success is, it’s blinding,” Mr. Winston adds, both in politics as well as in other arenas. “Because you are successful, you assume everything you did was correct.” That can cloud a person’s ability to critique his own performance – or improve on it.

Some Trump supporters themselves make a similar point. In focus groups and in interviews at rallies, some wish out loud that he would cut back on the tweeting and strike a more presidential tone.

The president and his defenders, including White House press secretary Sarah Sanders and son Eric Trump, argue that some of the comments deemed to be overly provocative or offensive were just meant to be entertaining.

When the president praised a Montana congressman last week for body-slamming a reporter during a special election last year, and mimicked the incident, Trump faced criticism for seeming to encourage a violent act.

The president’s son begged to differ. “Stop, he wasn’t the guy who body-slammed anybody,” Eric Trump said when questioned about the Montana rally during an appearance on Fox News. “He can have fun.”

Moreover, that was “exactly why my father won,” the younger Trump added. The public is tired of “perfectly scripted” politicians who memorize sound bites and have no charisma, he said.

Experts on presidential rhetoric say there’s something to the argument that the president is just trying to entertain his audience.

“It might not be a very good excuse, but in some of those instances, it may actually be true,” says Martin Medhurst, a professor of communication and political science at Baylor University in Waco, Texas. “This man is nothing if not a showman.”

Still, he adds, “it’s hard to distinguish that from his everyday practices of belittling, and name-calling, and all the things that are clearly not meant to be humorous.”

On the more serious question of whether the president can be held responsible for inciting violence, following the Pittsburgh massacre and the pipe bomb incident, Mr. Medhurst and others say it’s impossible to draw a direct line between a president’s rhetoric and another person’s actions.

But presidential rhetoric matters – especially at a time of growing political polarization, a trend that long preceded Trump’s election. 

“When you inflame threats, you don’t do much to help Americans come together,” says George Edwards, a political scientist at Texas A&M University in College Station, Texas, and author of a book on the presidential bully pulpit. “You can mouth a few words about, ‘We need to come together,’ but when the rest of the rhetoric does not encourage that, it reinforces social divisions that have been rising since Ronald Reagan’s day.”

Republicans argue that Democrats have also been guilty of inciteful language, pointing to former Attorney General Eric Holder’s statement, “When they go low, we kick them.” Then there’s former Vice President Joe Biden, who boasts that if he and Trump were in high school, he’d “take him behind the gym” and beat him up.

Indeed, and when a disgruntled gunman burst into a newsroom in Annapolis, Md., last June, killing five people, Trump wasn’t blamed – despite his rhetoric repeatedly attacking the media as the “enemy of the people.” In the Annapolis case, the gunman was known to have a specific grievance with the newspaper.

To critics, the “both sides” argument is a dangerous form of false equivalency. And it minimizes the fact that the president has the biggest megaphone in the world.

In the annals of the American presidency, Trump is unique in his ability to dominate public discussion, says Edwards.

But just as striking is the content of the message.

“Trump’s rhetoric is a rhetoric of fear,” Edwards says. “He emphasizes threats to personal safety – claims that violent crime is soaring, that Islamic terrorists are a dire threat – and to personal economic status, from foreign trade, global warming, immigration, regulation, the Affordable Care Act. All of these are going to ruin your life.”

Olivia Sheldon is one of those voters who’s still deciding who to vote for in a hotly contested Senate race. But she knows one issue she cares about a lot: health insurance.

“Health care definitely needs some work,” she says. “I would love to have some reform.”

Ms. Sheldon is an expectant mother who, at age 24, has a job in retail and is studying for a degree in psychology. And for this resident of the mountain town of Harpers Ferry, what’s needed doesn’t fit neatly on either side of a debate that typically pits ideals of government-provided care against reliance on free-market principles.

“I want the government support,” she says, citing the high costs of medical care. “But I want [government] out of the doctor’s office when I’m in for an appointment.”

Her views point toward an important reality of the 2018 election: No single issue looms larger on the campaign trail than health care ​– the subject of nearly half of all campaign ads for federal races. Voters want both low prices and high-quality care, and they show support for a strong government role on health policy, up to a point.

In this campaign cycle, one core tenet of Obamacare has moved front and center: that people shouldn’t face higher insurance prices because of preexisting conditions. Americans widely support that idea, and Democratic candidates have put Republicans on the defensive over the issue in key races such as the one here in West Virginia.

Yet even as a majority of voters say they trust Democrats more than Republicans on health care – and as proposals of “Medicare for all” gain a following in some quarters – policy experts don’t see an easy path toward meeting voter aspirations.

“There is not a magic bullet on health care, ...  regardless of what the political parties say,” says Chris Sloan, a director at Avalere Health, a Washington-based consulting firm. Referring to the Medicare-for-all idea, he adds: “It's not easy to create a single-payer system in the United States that saves a lot of money.”

What the parties are offering

The two major parties offer starkly different visions on health care.

Republicans focus on ever-rising costs and the risk to both individual pocketbooks and federal deficits. Their preferred solutions emphasize longstanding conservative ideals of consumer choice, competition, and flexibility for state-level innovation on policy. The Trump administration has moved to make slimmed-down insurance plans available to Americans who don’t feel they can afford Obamacare.

John Shaver/The Exponent/AP

Vice President Mike Pence (l.) and GOP Senate candidate Patrick Morrisey wave at a campaign rally in Bridgeport, W.Va., on Oct. 20. It was Vice President Pence's second stop in West Virginia in the past three months to stump for Mr. Morrisey, the state's attorney general.

But that, coupled with other moves, has left them vulnerable to attack – with GOP candidates scrambling to insist that they, too, support protecting people with preexisting conditions. At least in their rhetoric, the 2018 race has made it a principle both parties agree on, backed solidly by public opinion.

“Hardworking West Virginia families are hurting,” GOP Senate candidate Patrick Morrisey says in an interview on the campaign trail, noting “skyrocketing premiums.” He pledges to repeal President Barack Obama’s Affordable Care Act (ACA) – but then adds in the next breath, “we also need to protect people with preexisting conditions.”

Here in West Virginia, a state that Trump won by a wide margin in 2016, state Attorney General Morrisey is challenging incumbent Democratic Sen. Joe Manchin in a close race, though most polls have shown Senator Manchin leading.

Manchin, a former West Virginia governor who has long positioned himself as a centrist, symbolizes how Obamacare is no longer the liability for Democratic candidates that it’s been in past election cycles.

In one TV ad Manchin charges that a Morrisey-backed lawsuit against the ACA seeks “to take away health care from people with preexisting conditions.” The ad is tailor-made for this conservative-tilting state, as Manchin destroys a document representing the lawsuit – and sends an I’m-not-liberal signal by using a shotgun to do it.

Most Democratic candidates aren’t toting guns in their ads, but the health care emphasis here in the Mountain State has been echoed in other close congressional races across the nation. 

For most Democrats, the core ideal for health care policy is universal coverage – something Obamacare aspired to but didn’t achieve. As a next step, Democrats in solid-blue districts or states are pitching “Medicare for all.” But, as appealing as the idea of government-funded health insurance sounds to many Americans, many also question how to pay for it.

Questions in West Virginia

The skepticism is evident in Inwood, a small town in Northeastern West Virginia where Morrisey recently held a rally.

“I don’t think that’s realistic…. Where do you get the money,” says rally attendee D.J. Beard, referring to a single-payer (government) system. A resident of nearby Glengary, Mr. Beard says he’s registered as an independent and sees a role for government. He himself is on Medicaid and out of work due to a health challenge.

But he thinks Republicans “are looking out for the people” while, from what he’s heard from European acquaintances, single-payer is not a model for the US to aspire to.

His view hints at why Americans have given mixed responses when asked in polls if they’d support switching outright to a single-payer system. By contrast, polls have found majority public support for the idea of a public health-plan offered alongside other options. A CBS News poll this month found 65 percent of Americans in favor of that idea.

And a Pew Research Center poll last year found 60 percent support for the idea that it is government’s responsibility to ensure health care for all, up from 47 percent who felt that way in 2014.

“Those on the right just celebrate everything that Trump says,” says Scott Flanders, chief executive officer of eHealth, an online marketplace for insurance plans. “Those on the left want to brand anything that isn't the ACA as bad.”

He says the reality is more complex – that millions of Americans can’t afford Obamacare plans, that many are seeing premiums and deductibles soar even when they have insurance through their employer, and that “Medicare itself is headed toward an unsustainable path.” 

Still, for now Democrats appear to have momentum on the issue. They have fodder for saying Republicans have sought to undercut the ACA’s protections. The lawsuit Morrisey backed, along with officials from other states, seeks to overturn the whole law (including its guarantees that premiums won’t hinge on one’s medical condition) as unconstitutional.

In other races, GOP lawmakers are under attack for supporting legislation undercutting the ACA. Where Republicans say they’re still seeking to protect people with preexisting conditions, while promoting greater choice in insurance markets, Democrats say those safeguards are far from ironclad.

Meanwhile, more from Washington

The partisan battle over health policy has been ramping up in recent days.

The Trump administration has sketched a new plan aiming to tame prescription-drug costs within Medicare by linking prices to what’s paid in other advanced nations.

The administration also announced a move to let states get waivers from Obamacare, potentially opening the door to states using federal dollars to subsidize insurance plans that are cheaper, but which offer less coverage than ACA-compliant plans.

Already, another Trump move is expanding short-term health plans as a cheaper alternative to Obamacare. Critics call it “junk insurance” since the coverage isn’t complete. Mr. Flanders of eHealth argues the plans are a “constructive” adjunct to Obamacare, helping many of some 28 million uninsured Americans to afford some coverage rather than none.

Many Democrats meanwhile say that Medicare for all, paid for with cost controls coupled with some tax hikes, can offer solid insurance to every American.

It’s possible that a single-payer system could help the US cover more people at a lower overall cost, says Mr. Sloan, the policy expert at Avalare, but he adds, “it’s hard.”

“To do that, the United States would have to cut a lot of health care spending,” he says. And that could mean reductions in everything from drug prices to physician reimbursements to other areas where the US spends more than other nations. “There's a lot of stakeholders [and entrenched interests] in place that that would affect.”

Alexander Zemlianichenko/AP

Russian President Vladimir Putin (l.) and US National Security Advisor John Bolton meet at the Kremlin in Moscow on Oct. 23.

Not all arms-control agreements are created equal.

That’s adding further complexity, and uncertainty, to a critical period in world efforts to contain nuclear weapons. The stakes are high: the prospect of a new superpower arms race, and the possible emergence of two more nuclear powers in North Korea and Iran.

It might be called a tale of three treaties.

The first is the 1987 Intermediate-Range Nuclear Forces Treaty between the United States and the Soviet Union. Last week, National Security Adviser John Bolton confirmed Washington’s intention to pull out. The second is the 2015 international accord limiting Iran’s nuclear program. Next week, the US will reimpose sanctions on Iranian oil exports, and attention will focus on whether, or how long, Tehran will choose to keep its nuclear program on hold.

The third is Mr. Trump’s still-elusive deal to get North Korea to scrap its nuclear arms.

For former Soviet leader Mikhail Gorbachev, who signed the 1987 treaty, US retreat from both it and the Iran accord are part of a bigger picture, in which the whole architecture of international arms control is coming under threat. He has warned of a “new arms race.”

And he may prove right. But the specifics of each of the arms-control deals now in the spotlight suggest that, if so, it’s likely to be different from the old US-Soviet variety.

In the 1970s, a main focus of nuclear tension was the Soviets’ deployment of a medium-range missile called the SS-20. Capable of hitting all of Europe, it threatened to “decouple” the United States from its NATO allies. If the Soviets launched SS-20s, the only response for the US would be an intercontinental strike. That raised the question of whether an American president would risk New York or Washington to protect Amsterdam or Bonn.

In December 1979, NATO responded by deciding to deploy similar US missiles in Europe. But the tension only truly subsided with the INF treaty: a first for arms control, because it didn’t just limit such ground-based weapons. It mandated their elimination.

So why does the US want out? The advertised catalyst is Russian President Vladimir Putin’s violation of the INF accord with a new cruise missile NATO calls the SSC-8. But there’s another reason, involving the country Washington sees increasingly as its true superpower rival: China. The INF treaty, to which China wasn’t a signatory, prevents the US from deploying medium-range ground weapons in Asia, where they form the backbone of the Chinese Army’s missile force.

The Iran controversy is less about nuclear arms than geopolitics. The agreement was a trade-off: strict limits, subject to UN inspections, on Iran’s development of a nuclear weapon for a period of 10 to 15 years, in exchange for billions of dollars freed up through the easing of sanctions. There’s been no evidence Iran is cheating. But it has been testing new missiles, as well as providing financial and military backing to Syria’s President Bashar al-Assad and the Lebanese-based Shiite militia Hezbollah – neither covered by the nuclear deal, but both seen by the US as part of an expanding Iranian threat in the Middle East.

Where the INF agreement and Iran come together is in their potential implications for an eventual deal with North Korea.

The Trump administration’s view seems to be that a tough response to Russia on the INF treaty, and withdrawal from a “bad deal” with Iran that left issues like missile development and Hezbollah unaddressed, will strengthen its position in nuclear talks with North Korean dictator Kim Jong-un. A move by the US to deploy ground missiles in Asia would also increase its military leverage.

Yet those messages could be received differently by North Korea and by China, whose support is almost certainly essential to a successful nuclear deal. 

The Iran agreement is more restrictive, and its inspection regime more intrusive, than anything Kim Jong-un has so far been willing to countenance. And that agreement has been working. So the Americans’ withdrawal could be seen in Pyongyang as calling into question their trustworthiness as negotiating partners. A beefed-up US missile force might raise an even more serious question in Kim’s mind: whether what Washington really wants is not just a non-nuclear North Korea, but a non-Kim one.

New to Toronto, I get asked many questions: about how I find the schools or the public transportation system. There’s another topic that has come up with confusing frequency too.

“Have you ever experienced Halloween in Toronto?” asked one father in the schoolyard in the still balmy days of September. “Enjoy your first Halloween in Toronto,” said a Spanish journalist when I introduced myself as a newly arrived colleague.

By October the house decorations in my neighborhood came out, giving the impression that every other home is inhabited by that one Halloween-crazed family on your street. There are ghosts and goblins hanging from trees, plastic gravestones peering out from flower beds and severed hands strewn across front lawns. Neighbors have giant blow-up cats and spiders on their front porches and have wrapped their front doors in bright yellow “caution” and “danger” tape. This is not just a single fanciful block; this is the entire neighborhood.

When I asked a woman two doors down about it, she said she’d be celebrating and decorating her house too. “For the community,” she explained.

Never a fan of the holiday, this year I found myself at the dollar store purchasing that “danger” tape – not for me, but for the people who walk past my front door.

There’s nothing particularly distinctive about the way Canadians celebrate Halloween, a tradition that has its roots in paganism, was Christianized, and then commercialized in North America. Yet perhaps, at least in my neighborhood, it seems to be more about togetherness than any great passion to don a witch’s hat or string some cobweb around the shrubbery.

Folklorists trace Halloween back to the Celtic festival of Samhain (pronounced sow-in). Nicholas Rogers, in his book “Halloween: From Pagan Ritual to Party Night,” says the feast marked the midpoint between the autumn equinox and the onset of winter, a time of stock-taking and preparations.

Halloween came to North America with Irish and Scottish migration in the 19th century and underwent many iterations. “Halloween’s capacity to provide a public space for social inversion or transgression held it in good stead at a time when other potentially raucous holidays were becoming more institutionalized and domesticated,” argues Mr. Rogers. It morphed from a family affair to a party co-opted by adults, and later to a time to reaffirm gay and feminist values.

In popular culture, Halloween is viewed as an American secular holiday. According to digital coupon company RetailMeNot, 73 percent of Americans plan to celebrate it this year. But it’s a phenomenon in Canada too. “It’s become bigger and more celebrated than it ever has,” says Chris Ainsworth, who founded the Canadian Haunters Association, a group of hardcore Halloween enthusiasts who turn their homes into elaborate haunted houses each year.

In 2014, the Retail Council of Canada made news saying Canadians were now outspending Americans per capita on Halloween, to the tune of $1 billion annually. The estimate has remained stable, says Diane Brisebois, the council president. That’s not because enthusiasm has waned, she says, but because prices have been driven down.

Some here bemoan the creep of the commercial in the festivities. But in some ways the holiday has also returned to its roots as a community-centered activity.

And perhaps that's why everyone gets so excited about Halloween in Toronto, a metropolis that is known as a “city of villages.”

In my neighborhood, Halloween revolves around two-block Lavinia Avenue, dubbed “Halloween Street,” where residents say they have to get help handing out candy to the children who pack the pavement every year. In the past two years they have moved it beyond just a boon to candy manufacturers, starting a food drive for the Daily Bread Food Bank. “If we are doing it as a community event, we decided we should make it more of a community event beyond massive commercialization,” says Alexandra Devlin, a mother of three young children on the street.

Some of her neighbors will take off an afternoon of work to decorate their homes, even hire an electrician to rig lighting and sound effects. She admits she finds the obsession with Halloween a bit strange. Yet she participates willingly – again because she is part of the community.

Ms. Brisebois agrees there is something to the “community spirit” behind Canadians' embrace of Halloween. “Canadians still like to meet their neighbors, to talk, to share, it is a Canadian trait, so Halloween is another way of getting a bit closer,” she says. “Maybe the biggest difference between Canadians and Americans is that Canadians really get excited, all hyped up about Halloween, I don’t know if it’s because of our weather and the thought that winter is coming, but people really embrace it.”

And as Ms. Devlin puts it, there is no middle way, at least on “Halloween Street.” “You are all in,” she says, “or you best turn off your lights and go to the movies for the night.”

AP

People listen at an interfaith vigil in Pittsburgh to honor those impacted by Saturday's shootings at the Tree of Life Synagogue.

One of the world’s most successful efforts at persuading terrorists or would-be terrorists to “disengage” from extreme militancy is in Denmark. The program aims to prevent Muslims from being radicalized and to reintegrate those who abandon terrorism back into society. But the approach could apply equally to almost anyone lured by a violent ideology – including Robert Bowers before his attack on a Pittsburgh synagogue.

His radicalization toward anti-Jewish white supremacy has many causes, including the rise of hateful rhetoric in social media and politics. Yet it is just as important to focus on the missed opportunities at preventing such terrorist acts.

Could Mr. Bowers’s murderous intent have been detected by family, friends, social media companies, law enforcement, or others? If so, what might they have said to him?

Would they have expressed moral outrage at his views and threatened to banish him? Or, as the program in Denmark does, would they have approached him on the premise that he aspires to a “good life” and simply needs quality relationships and the skills of resiliency to deal with life’s challenges?

Denmark’s program relies heavily on private and local initiatives to disengage radicals. Surveillance by government of an individual’s risk of violence poses its own difficulty. A helping hand or a kind word of warning from a community leader, religious figure, or mental health expert can often turn around someone bent toward destruction in the name of a cause.

Such persons may not end up being “de-radicalized” in their ideology. Yet given a supportive and loving community, they could desist from causing harm. They might look elsewhere than violence to achieve meaning, honor, or empowerment.

Reaching such individuals is not that difficult. In a 2014 study of 119 terrorists who acted alone, their grievances and their commitment to an ideology were known to family and friends in nearly two-thirds of the cases. In 59 percent of cases, the offender made public statements prior to his or her violent act, according to the study, which is titled “Bombing Alone.”

In addition, the profile of would-be terrorists is pretty clear. Half of them changed addresses at least five years prior to their terrorist planning. Of the 40 percent who were unemployed, a quarter had lost their jobs within six months. A third showed elevated levels of stress.

“These findings suggest that friends, family, and coworkers can play important roles in efforts that seek to prevent or disrupt lone-actor terrorist plots,” the researchers concluded.

In other words, we are all counterterrorist agents, yet perhaps different in how we would approach people who appear radicalized to the breaking point. Will we present the “good life” to those on the fringes? Or push them off the edge?

“Our greatest strength lies not only in what we do but who we are and the values and freedoms we hold dear,” says Britain’s Home Secretary Sajid Javid. “That is why everyone has a part to play in confronting terrorism.”

The Danish program, known as the Aarhus model for the town where it is located, happens to be one of the most successful. Yet with the rise of “lone” terrorists since 2008, other countries have emphasized a “soft” approach. The aim is to modify behavior by offering an alternative to hate, one based on the good that binds people. Like the name of the Pittsburgh synagogue, we all are part of the tree of life.