Editor’s Note: Norman Eisen (@NormEisen), a former ambassador to the Czech Republic and ethics czar to President Barack Obama, was special impeachment counsel to House Judiciary Committee Democrats in 2019-2020. Katherine Reisner (@katiereisner) was counselor to the secretary and deputy secretary at the Department of Homeland Security in the Obama administration, and is a Truman National Security Project Fellow. Both serve as outside counsel to the nonpartisan Voter Protection Program. The opinions expressed in this commentary are their own. View more opinion on CNN.

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Now that Donald Trump and his defenders have failed (again) to persuade the Senate that an ex-president cannot be impeached, the trial of the former president will begin in earnest. The House managers who foreshadowed their opening argument on Tuesday and will present it in full on Wednesday and Thursday have the best of the facts and the law. But can they solve the political problem of wooing 17 GOP senators to get to the two-thirds majority of the Senate necessary for conviction?

That won’t be easy, but they won over another Republican senator Tuesday. Trials are full of surprises and we should reserve judgment on the final outcome here.

As is clear from their trial brief and their advocacy Tuesday, the impeachment managers will make the case that Trump incited insurrection over the course of months, building up to January 6, and that this incitement of insurrection meets the “high crimes and misdemeanors” standard for conviction and disqualification from future federal elected office.

They will argue that Trump’s fomenting of violence against the Capitol was an attempt to extend his grip on power in violation of his oath of office. His incitement of insurrection on January 6 was only the latest in a long series of actions he took to try and subvert the democratic process, again in violation of his duty as president.

As the managers’ gripping video showed, Trump’s behavior threatened not only the institutions of democracy but also then-Vice President Mike Pence, nearly the entire Congress, and thousands of staff and security personnel in the Capitol complex. Five people died. In all of this, Trump undermined the national security of the United States.

Not only did the insurrectionists physically remove electronics and sensitive material from the Capitol, they also, according to the Department of Homeland Security, emboldened other domestic extremists. Trump’s own behavior also tarnished the reputation of the United States overseas.

The Framers “anticipated impeachment if a President placed his own interest in retaining power above the national interest in free and fair elections,” the managers wrote in their pre-trial brief. From the time of the country’s founding, it has been well understood that “betrayal of the Nation’s interest — and especially for betrayal of national security,” warrants his conviction, they continued. They hammered that point home on the first day of the proceedings.

Trump’s defense attorneys make three core arguments — also alluded to on Tuesday — as to why the former president’s actions and words are not high crimes. All are unavailing. First, they argue in their filings that because Trump called upon supporters to “peacefully” make their voices heard, this negates his other exhortations to lawlessness.

The problem is that Trump did use the word “peacefully” in his instructions to the crowd, but not until after he had already exhorted them to among other things “show strength.” He followed up the call for peacefulness with further calls for lawlessness, closing his remarks with a call on supporters to “fight like hell” — the 20th time he referenced fighting in that speech. Trump had for weeks been encouraging supporters to arrive at the Capitol on January 6, tweeting “Be there, will be wild!” Trump’s isolated request for peacefulness cannot un-ring the bell.

Trump’s attorneys will also argue that Trump could not be responsible for inciting the insurrection because there is evidence that the insurrection was pre-planned. “The real truth is that the people who criminally breached the Capitol did so of their own accord and for their own reasons,” Trump’s team asserts in their pre-trial brief.

This is absurd. Two things can be true: That many of the thousands gathered had come ready to perpetuate violence, but also that they and others were spurred into lawless action by their then-president exhorting them to “fight like hell.” Indeed, the insurrectionists themselves have told law enforcement officers that they were “merely following the directions of then-President Trump,” as did a man accused of discharging a fire extinguisher at police, and many other alleged insurrectionists.

Finally, Trump’s defense will argue that Trump’s exhortations were not, in fact, calling for actual lawlessness. They were figures of speech. While it is true that the word “fight” can be used figuratively, the context here is critical.

In this case, for the crowd gathered before then-President Trump to make good on his exhortation to “stop the steal” — there was literally only one way to effectuate this call to action: to impede the counting of electoral votes that would shortly occur in the Capitol. After months of whipping his followers into a frenzy, his message on January 6 was perfectly clear, and his lawyers’ claims that he was just talking about election security are absurd.

Despite the strength of the House managers’ argument and the weakness of Trump’s, persuading 17 Republican senators will not be easy. Still, there are some advantages that we did not have in the prior impeachment and trial, where one of us served as co-counsel for the managers.

On Tuesday afternoon, six Republican members of the Senate signaled a degree of openness to conviction by rejecting the argument that the Senate lacks jurisdiction over the case — an addition of one more Republican since last month’s similar vote on whether to dismiss the trial as unconstitutional. And the American people are much more supportive here, with 56% favoring conviction versus the 47% of Americans who supported conviction at the outset of Trump’s earlier impeachment trial, last year.

We can expect some “trial magic” to attempt to expand those numbers. The impeachment managers will mount a dayslong Ken Burns-style miniseries, likely including never-before-seen video of witnesses and events. As one of us saw firsthand, the video at the prior trial transfixed the Senate jurors, and the evidence here will be more compelling. That was demonstrated by the short video shown early in Tuesday’s proceedings, and there is much more to come. And this time, the Senate jurors themselves are both witnesses to and victims of the crime and are sitting in the chamber that was the scene of that crime.

The impeachment managers’ task is to summon the jurors back to what they felt that day, and ask: How do you want history to remember you? As the senator who allowed the former president, the insurrectionist-in-chief, to evade sanction? To run for office again? To continue his dragging democracy down?

There is more than enough testimony on video to make that case to the Senate, including not only Trump’s words but the attackers admitting they acted at his behest. Nevertheless, other key witnesses may yet step or be called forward. If there were no possibility of such surprise witnesses, the opportunity for a vote on them would not have been included in the organizing resolution.

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    In working their way through all this, impeachment managers will remain keenly aware that they are addressing two audiences: The jury of 100 senators, of course, but perhaps more importantly, that of the American people. The voting public put Trump out of office after the Senate failed to convict him during his first impeachment and trial; the electorate will again be the ultimate judges of Trump’s conduct if the Senate again fails to convict.

    This trial will be the single best means of providing the American public — the true sentinels of democracy — with the record we all deserve so that we may render a fully informed decision about Trump, should he seek to run again.