AMID THE IMPEACHMENT FUROR, don’t lose sight of the renewed importance of protecting the integrity of the 2020 election.

The difference between Richard Nixon’s abuse of power (trying to get dirt on political opponents to help with his 1972 re-election and then, covering it up) and Donald Trump’s abuse of power (trying to get Ukraine’s president to get dirt on a political opponent to help with his 2020 re-election and then, covering it up) isn’t just that Nixon’s involved a botched robbery at the Watergate office complex while Trump’s involves a foreign nation.

It’s that Nixon’s abuse of power was discovered during his second term, after he was re-elected. He was still a dangerous crook, but by that time, he had no reason to inflict still more damage on American democracy.

Trump’s abuse has been uncovered 14 months before the 2020 election, at a time when he still has every incentive to do whatever he can to win.

If special counsel Robert Mueller had found concrete evidence that Trump had asked Russian President Vladimir Putin for help in digging up dirt on Hillary Clinton in 2016, it would have been the smoking gun that could have ended the Trump presidency.

Now that Trump is revealed to have asked Ukrainian President Volodymyr Zelensky for dirt on Democratic candidate Joe Biden for the 2020 election, who’s to say Trump also isn’t asking others? Is he soliciting Putin’s help this time around?

The Washington Post reported late last week that Trump told Russian officials, in a 2017 meeting in the Oval Office, that he was unconcerned about Moscow’s interference in the 2016 U.S. election. White House officials limited access to these remarks, as they did to Trump’s outreach to Zelensky.

American intelligence warned that Russia will continue to try to interfere in our elections. Senate Majority Leader Mitch McConnell has agreed to add just $250 million to protect election machinery from cyberattacks, while experts said billions are needed.

Trump also is in a better position to make such deals than he was in 2016, because as president, he’s got the power and money to make any foreign ruler’s life exceedingly comfortable or uncomfortable.

As we’ve learned, Trump uses whatever bargaining leverage he can get for personal gain. That’s the art of the deal.

Who can we count on to protect our election process in 2020?

Certainly not Attorney General William Barr. Trump urged Zelensky to work with Barr to investigate Biden, even telling Zelensky that Barr would follow up with his own phone call.

Barr’s Justice Department decided Trump had not acted illegally and told the acting director of national intelligence to keep the whistleblower complaint from Congress.

This is the same attorney general who said that Mueller’s report cleared the Trump campaign of conspiring with Russia when in fact, Mueller had found that the campaign welcomed Russia’s help; and that Mueller absolved Trump of obstructing justice even though Mueller specifically declined to decide the matter.

Barr is not working for the American people. He’s working for Trump, just like Rudy Giuliani is working for Trump, as are all the other lapdogs, toadies and sycophants.

Fortunately, some government appointees still understand their responsibilities to America. We’re indebted to the anonymous intelligence officer who complained about Trump’s phone call to Zelensky and to Michael Atkinson, inspector general of the intelligence community, who deemed the complaint of urgent concern.

But if the 2020 election is going to be and be seen as legitimate, the nation will need many more whistleblowers and officials with integrity.

States must upgrade all election machinery and equip them with paper ballots that can be audited. Facebook and YouTube must devote more resources to protecting against malicious bots.

All of us will need to be vigilant.

Over the last two-and-a-half years, Trump has shown himself willing to trample any aspect of our democracy that gets in his way: attacking the media, using the presidency for personal profit, packing the federal courts, verbally attacking judges, blasting the head of the Federal Reserve, spending money in ways Congress did not authorize and subverting the separation of powers.

Trump believes he’s invincible. He’s now daring our entire constitutional and political system to stop him.

The real value of the formal impeachment now underway is to put Trump on notice that he can’t necessarily get away with abusing his presidential power to win re-election. He will still try, of course, but at least a line has been drawn. And now, everyone is watching.

Regardless of how the impeachment turns out, Trump’s predation can be constrained as long as his presidency can be ended with the 2020 election. If that election is distorted and this man is re-elected, all bets are off.

Robert Reich’s latest book is “The Common Good” and his newest documentary is “Saving Capitalism.”