In this Dec. 22, 2017, file photo President Donald Trump signs into law a $1.5 trillion tax overhaul package in the Oval Office of the White House in Washington. New rules floated by the Trump administration lay out what kinds of businesses can take a 20 percent deduction against income taxes under the new tax law. With the proposed rules issued Wednesday, Aug. 8, 2018, the Treasury Department and the IRS had worked for six months to bring clarity to Congress' blueprint. 

Almost 55 years ago, President John F. Kennedy was gunned down on his way to deliver a speech to the Dallas Citizens Council.

The Democrat was heading into unfriendly, to him, territory populated by a lot of angry partisans, some of whom spat on his vice president’s wife during the 1960 campaign and whacked on the head his United Nations ambassador the month before.

Kennedy had planned to address the divide head-on.

In the speech he never gave, Kennedy planned to say:

“In a world of complex and continuing problems, in a world full of frustrations and irritations, America’s leadership must be guided by the lights of learning and reason — or else those who confuse rhetoric with reality and the plausible with the possible will gain the popular ascendancy with their seemingly swift and simple solutions to every world problem.”

Investigators at the time, and for decades afterward, attached all sorts of political motives to the assassination. Ironically, opportunity seems to have been more important than the muddled politics of the psychotic who pulled the trigger of an Italian military carbine rifle bought through the mail.

Though Kennedy’s words a half-century ago seem prescient today, American politics always had a violent side. This is the country, after all, where in July 1804 a sitting vice president killed a former Treasury Secretary in a duel after Federalist Alexander Hamilton viciously defamed Democratic-Republican Aaron Burr during the campaign for New York governor that year.

Violence is a worry for President Donald Trump going into the midterm congressional elections about nine weeks away. Trump invoked Antifa, a coalition of liberal groups whom conservatives blame for political violence, when he asked evangelical leaders Monday to rally their congregations for an election that pundits say could end up with Democrats in control of one or both chambers of Congress.

"This Nov. 6 election is very much a referendum on not only me, it's a referendum on your religion, it's a referendum on free speech and the First Amendment. It's a referendum on so much," Trump told the pastors who had gathered behind the closed doors of the State Dining Room, according to a recording CNN obtained.

"It's not a question of like or dislike, it's a question that they will overturn everything that we've done, and they will do it quickly and violently. And violently,” the president said.

Despite lapses that would have condemned another politician, evangelical Protestants provided key support that put Trump in the White House.

Trump has cause to be concerned about their steadfastness as the newly elected head of the Southern Baptist Convention, the nation’s largest Protestant denomination with 16 million adherents, earlier this summer said the church needed to “decouple” its close association with Republican orthodoxy if the Baptists hoped to stem the decline in congregations.

“If we want the SBC to be a homogeneous, conservative, white Anglo-Saxon movement, then cultural hegemony is fine. But if we want to reach the diversity of communities throughout the United States, then we better get ready to see our cultural and leadership structures change,” said the Rev. J.D. Greear, of Raleigh, North Carolina, the new Baptist leader.

Louisiana, safely in the Republican corner, is not on Trump’s pre-election barnstorming of 11 states.

But evidence of erosion, however slight, was voiced by the Rev. Gene Mills, head of the powerful Louisiana Family Forum, which pushes the Legislature to adopt laws that limit gay rights, expand barricades to abortion, and oppose gambling, along with other cultural issues.

Mills said Monday he likes Trump’s judicial nominees but doesn’t like “the coarse manner in which he (Trump) communicates," which turns off many evangelicals. 

As Mills spoke to reporters at a Baton Rouge casino and Trump spoke to evangelicals at the White House, the president’s staff debated whether to return the flag to half-staff to honor Arizona U.S. Sen. John McCain, a maverick Republican, war hero and frequent Trump critic who died Aug. 25.

McCain's last words in public, a letter his daughter tweeted, warned of the impact political divisions have on America.

“We weaken our greatness when we confuse our patriotism with tribal rivalries that have sown resentment and hatred and violence in all the corners of the globe,” McCain wrote. “We weaken it when we hide behind walls, rather than tear them down, when we doubt the power of our ideals, rather than trust them to be the great force for change they have always been.”

Follow Mark Ballard on Twitter, @MarkBallardCnb.