The country is so politically divided that people increasingly are not tolerant of different views or respectful of others. This is not simply a lack of good manners. It is a blow to a democratic society.

After a half century’s involvement in Washington policy-making, mostly working as counsel for a Congressional committee, I am returning to my home town of Chicago. Reflecting on those years, I see growing incivility based on political differences.

In 1967, when I arrived in D.C., congressional push-back was shaking support for President Lyndon Johnson’s racial and social equity policies. The previous year’s election had gone against the Democrats, and the Republicans were fighting hard against the civil rights laws and programs like Medicare.

In addition, Richard Nixon was campaigning for the presidency which he won the next year. Despite that victory, he nursed resentment against Democrats for denying him that office eight years earlier through alleged vote fraud. In 1974, he resigned because of his own alleged crimes.

Similarities exist between that period fifty years ago and 2017, but worse. Last year’s election went against the Democrats, and congressional conservatives are assailing President Barack Obama’s social equity policies of universal health care and higher taxation of the wealthiest citizens.

Like Nixon, President Trump is facing impeachment due to his alleged illegal actions. Trump, too, resents those who oppose him.

A big difference between the two eras, though, is today’s sharply divided society. Members of Congress, the news and social media, ordinary citizens, and the country’s leader demonize those with contrary opinions. This is not an occasional slip of tongue, rather, this is common behavior. For example, a chant encouraged at Trump rallies was “Jail, Hillary.”

In 1967, that level of hostility and hate was not the usual practice of politicians, opinion-makers, or ordinary citizens. Since then, a toxic transformation of politics has fed an intolerance of those with different opinions.

That toxicity arose from a lowering of ethical standards in politics. This occurred right in front of us, and we did not demand an end to it.

The current slide to unethical conduct began with a single, nasty political ad used in 1964 by Lyndon Johnson against his opponent, implying that nuclear war would follow a Barry Goldwater victory. In his campaigns, Richard Nixon went further developing a whole stock of dirty tricks, which became the handbook for subsequent Republican presidential candidates.

Democratic as well as Republican presidential candidates raised funds however they could, sometimes skirting ethical boundaries. But, Republicans went a giant step further and purposefully based their national campaigns on dirty, divisive tricks.

Since the news media always seeks to give balanced coverage (except for Fox and company), this pattern of bad behavior by the Republicans was not established as theirs alone. “Fairness in reporting” trumped honesty, leaving the impression that both parties acted the same. They did not.

The Republican handbook used prejudice against racial, ethnic, and sexual minorities in cleverly packaged campaign ads that won elections. Bold-faced lies came shamelessly from conservative radio commentators, Fox news, and other outlets. The social media, which lacks the means of truth-checking, facilitated wide dissemination of these untruths. A result has been the splintering of the public into fractions who only get information from and communicate with those who agree with them.

This repugnant behavior was not condemned by religious leaders because many of the policies they advocate were supported by the offenders. Republican leaders generally did not admonish fellow party members because their own success was helped by this conduct.

Changes in society created fertile ground for support of such base methods. Increased immigration of peoples not of European stock frightened whites who saw themselves becoming a minority. The decline in manufacturing jobs eliminated a path to the middle class for many near-poor and lower middle class people, sowing the seeds of anger and resentment.

This unethical conduct by the Republicans reached its low point in the last election. President Trump’s incendiary and insulting opinions and the Tea Party’s tactics gave them electoral success; but, at the price of further dividing the United States. Our country is becoming a nation of tribes fighting one another for advantage.

Among Democrats, these Republican tactics have created a counter-force that is fighting back, mimicking the Tea Party’s ideological and strident tactics. Although this fight may balance the debate, will the political left add to the damage to our democracy through intolerance of other views and demonizing the opposition?

Did the Republican Party lose its soul in a Faustian bargain to gain and retain power? Will the Democrats do likewise? Can they fight without adopting the same unethical tactics as the Republicans have used for half a century?

Amidst this political maneuvering, tolerance of other points of view and respect for others as fellow citizens must be a conscious goal. That may seem completely unrealistic in a time of such raw emotions.

Russian connections, use of public office for personal gain, and budgetary heartlessness do not encourage a reasonable response from others. But, the Democrats must listen to their better natures, while Republican leaders should examine their behavior.

Grover Norquist’s organization, Americans for Tax Reform, has been very successful in stopping tax increases by demanding that candidates for public office sign a pledge that they will not raise taxes. Signatories include a majority in Congress.

Can this same tactic help with restoring tolerance and respect? Every candidate for public office could be asked to sign a “civility pledge” to act toward others with tolerance and respect.

In light of the harsh politics in the country, this is a small step, but the intent is large–to have us stop for a minute and think. The U.S. is on its way to creating divisions like those seen in Northern Ireland among generations of Catholics and Protestants and in the Middle East among Israelis and Arabs.

Do not for a second believe that those extreme conditions are impossible in America. The Civil War of the 1860’s, the worst conflagration our country ever experienced, was the result of increasingly bitter political debates that spiraled into massive, gruesome armed conflict.

Civility is a virtue that we all ought to practice, even if it means swallowing hard while we do so. Americans must act toward one another with respect and tolerance—and demand that our elected officials do likewise.