Let the facts from Mueller's investigation exonerate or prove wrongdoing by President Trump Escalating attacks on the rule of law concern Sen. John McCain - and they should concern you, too, regardless of your politics.

Grant Woods | Opinion contributor

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Sen. John McCain's moving call for a renewal of public civility embodies leadership that keeps faith not just with American ideals, but with American institutions.

He has set a lifelong example as a statesman who can disagree with his colleagues but revere the Senate, a senator who can oppose the foreign policy of a president and keep faith with the men and women of the military.

McCain has fought for our institutions because he knows that America endures because of our institutions. The Constitution, separation of powers, an independent justice system and the rule of law have always been principles, in McCain’s words, “worth the fighting.”

Today, these principles are under attack and sustaining damage that may last generations.

It's dangerous to call a legal system 'corrupt'

Over the past months, President Trump has repeatedly called special counsel Robert Mueller’s investigation a “witch hunt,” denigrated the Department of Justice and ridiculed the FBI. He and his surrogates have smeared elements of our justice system as “dishonest,” “corrupt,” and “rigged.” They have likened FBI agents to Nazi stormtroopers.

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If these attacks on our legal system continue unabated, the consequences will be catastrophic.

All Americans should support the rule of law and the ability of critical institutions — including the special counsel, the Department of Justice, and the FBI — to proceed without politicization.

No matter who you voted for, the escalating attacks on the rule of law should concern you, because the justice system in America relies on the faith of all of us.

McCain stood up for his ideals

It’s not surprising that McCain has stood up to forces seeking to erode confidence in the things that safeguard our liberty. But more leaders need to follow his lead, and more action must be taken.

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We must always be a “nation of laws, not men.” That’s an ideal that separates the United States from countries led by dictators and despots. It’s an ideal that brings thousands of foreign judges, attorneys, and prosecutors to the United States every year to study and marvel at our incredible system.

It’s all in jeopardy today.

Ronald Reagan said “freedom is always one generation away from extinction;” so, too is public faith in our cherished institutions. It’s not automatic, we have to protect it with all our might.

No one — not even the president — is above the law, and the special counsel investigation must be allowed to proceed without political interference.

Let Robert Mueller finish the job that he is unquestionably qualified to do. Let the facts exonerate or prove wrongdoing, but don’t let political interference turn us into the kind of country where the rule of law can be dismissed.

We all are responsible to stand up for our institutions and ideals, and we will all be measured by whether we did so in America’s time of testing. We are living one of those moments. Insist that our elected representatives speak out and take action to prevent unalterable damage.

Congress should pass a bipartisan bill to protect the special counsel’s investigation from political interference, and the Arizona congressional delegation should support it. We owe that much to McCain and the country he has served so well.

Grant Woods is a former Arizona attorney general. This column originally appeared in The Arizona Republic. Follow him on Twitter: @GrantWoods.