As Benjamin Franklin left the Constitutional Convention in 1787 he was approached by a woman who asked: “Well, Doctor, what have we got — a republic or a monarchy?”

“A republic, if you can keep it,” replied Franklin.

On the eve of the Senate impeachment trial of President Donald Trump, we face that question once again.

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Trump has been impeached by the House. Now, the Senate will determine whether he should be removed from office based on two articles of impeachment: abuse of power and obstruction of Congress.

Trump stands accused of soliciting a foreign government’s help to defeat a political opponent in 2020 and withholding congressionally approved military aid until that assistance was provided. When Trump was first confronted last September about his request to Ukraine President Volodymyr Zelensky, he released a summary of the call that prompted the impeachment inquiry. Since then, a parade of witnesses has, under oath, testified, adding more evidence to the case that Trump’s call constituted asking a foreign government to interfere in our election.

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No one can solicit, accept or receive anything of value from any foreign government for a U.S. political campaign. That is the law. And Trump’s withholding of funds appropriated by Congress for Ukraine is in violation of the law, as the Government Accountability Office (GAO) found last week. “Faithful execution of the law does not permit the president to substitute his own policy priorities for those that Congress has enacted into law,” the GAO wrote. “The Constitution vests lawmaking power with the Congress.”

The request to interfere in the 2020 election and the denial of aid to Ukraine are the basis for the article on the abuse of power.

Trump’s obstruction of Congress is equally clear.

From the beginning, Trump has blocked requests for testimony, documents and witnesses. Even the transcript of the call, which the White House claims was complete, was edited.

If Trump did nothing wrong, he should have let administration officials testify before the House committees investigating the call. It’s not too late. Former National Security Adviser John Bolton, Acting Chief of Staff Mick Mulvaney, and other relevant witnesses can still appear before the Senate trial. But as the trial prepares to open this week, there is still no guarantee that witnesses will be called.

The fact is a full and fair trial could reveal more evidence of wrongdoing by Trump and members of his administration. This can’t be ignored.

Let’s remember that for months Trump insisted he wanted a full trial, with witnesses, testimony and evidence. Until eight days ago. Trump apparently changed his mind, realizing it could be incredibly damaging to him and result in an outcome he can’t control.

Yet 71 percent of voters, the majority of Democrats, independents and Republicans, want witnesses, testimony and evidence. If Republican senators don’t vote to include them, they will pay a tremendous price with voters, especially vulnerable senators up for reelection this year, including Senate Majority Leader Mitch McConnell of Kentucky, Susan Collins of Maine and Cory Gardner of Colorado.

The fact is a full and fair trial could reveal more evidence of wrongdoing by Trump and members of his administration. This can’t be ignored.

The process about to unfold was designed by patriots who began this great American experiment over 220 years ago. Checks and balances. Law and order. It is patriotic to hold those in power accountable. These principles have given us the greatest government made on earth. The same government that has helped unleash democracy around the world. The government we have defended in war and peace. It is a beacon of hope that has survived economic catastrophes, natural disasters, and enemies foreign and domestic. And we are still standing.

But for how much longer?

At the Constitutional Convention, the preamble declared to all the world who would govern in these United States:

“We, the people in order to form a more perfect union, establish justice, insure domestic tranquility, provide for the common defense, promote the general welfare, and secure the blessings of liberty to ourselves and our posterity, do ordain and establish this Constitution for the United States of America.”

So what will it be in 2020? We the people? Or one person?

A republic. Or a monarchy? Or worse?

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A republic, if you can keep it.

We are about to find out.

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