07/31/2016 10:37 am ET Updated Aug 01, 2017

A Citizen's Letter to Hillary Clinton and Donald Trump

After a long and contentious process, you have won the nomination. Yet during that same process, Americans have lost. You need to know that. This letter is a plea to keep it in mind during the general election campaign.

I have always believed in our system of government. I have devoted my professional life to it, first in the Air Force and then in civilian service. I know we have faults, having lived through the struggle for civil rights, the divisions of Vietnam, political assassinations, Watergate, and the partisan fighting of the last three decades. But each time, it seemed, we were able to stop the shouting and find enough common ground to heal and move forward.

It does not seem so now. We no longer just differ on issues. Too many don't believe their political opponents - and many of their fellow Americans - are even worthy of respect. Instead of debating, they demonize. Instead of drawing different conclusions from the same facts, they search for only those facts that support them. They see the political system not as a way to resolve arguments but as an enemy, forgetting that when they delegitimize it, they leave us with nothing else to use. They see the Constitution not as a set of values and rules to responsibly resolve differences but as a tool to quote from to bludgeon opponents.

So this is my plea. Don't make this problem worse. Don't divide our country. Demand that your supporters don't either. I know elections are won by drawing distinctions between your opponent and you, including on issues of character, but you don't have to stoke hatred through cruel insults, crude language, and remarks that demean each other and other Americans.

Two of our greatest presidents, Washington and Lincoln, deserve that honor because one of them, a model of prudence and respect, created fidelity to our new form of government and the other restored it. They also sought to unite Americans - as Lincoln put it, with "malice toward none, with charity for all." Be that kind of politician.

Remember that how you campaign determines your ability to govern. The electoral process is aimed not only at providing a winner but at forming a government that has legitimacy. If you use the next three months to tear America apart, half of America will hate you even if you win. Four years will not be time enough to put us back together.

What if you want to run a respectful campaign, but your opponent will not? This is another part of my plea: display moral courage, a quality essential in a president. Run a campaign that honors America. Even if you lose, we need your example. It might shame your opponent into being respectful (or risking defeat for failing to do so). Do what is right for us, even if it seems wrong for you.

Restore our faith in truth. Many Americans think you lie. You need to accept responsibility for this. When you are selective with facts and spin the truth, you break the bond of trust. Without trust you cannot govern. Even worse, you convince many that there is no such thing as truth, that every fact is a fiction. We cannot solve our problems if we have no respect for facts.

Finally, be a candidate for all Americans. You can't be if you think that winning a majority means you can ignore the minority. That's what your detractors fear. In your campaign, you need to demonstrate the ability to respect and find some common ground with those who disagree with you.

When Gerald Ford took the oath after Nixon resigned, he said: "As we bind up the internal wounds of Watergate . . . let us restore the golden rule to our political process, and let brotherly love purge our hearts of suspicion and of hate." A month later, Ford pardoned Nixon to heal the nation, even though it might (and eventually did) cost him the presidency in1976. That is a model of leadership too rare in politics today.

Please, Ms. Clinton and Mr. Trump, run a campaign that strengthens America.