Comparing Donald Trump to Richard Nixon is unfair — to Nixon Watergate was about a domestic political break-in. Kremlingate is far darker and more consequential.

Max Boot | Opinion columnist

Kremlingate, the scandal involving the Trump campaign’s possible ties to Russia, has already led to the firing of the FBI director, the appointment of a special counsel and hints that the president may fire the special counsel, too. Naturally this has prompted comparisons to Watergate. But the comparison is unfair — to Richard Nixon.

President Trump's situation is much more serious. He isn’t just accused of covering up a “third-rate burglary,” as White House spokesman Ron Ziegler described the break-in at the Democratic National Committee’s headquarters 45 years ago this month. He's being investigated for possibly obstructing an investigation into his associates. And they're being investigated for Russia connections as a result of a far more extensive break-in into the computer systems of the DNC and the Hillary Clinton campaign that was perpetrated by Russian agents.

The wiretapping of the DNC, even if successful, would not have had much impact on the 1972 election, which Nixon won in a landslide. The 2016 election was much closer — decided by just 80,000 votes in three states — and Trump touted the Clinton campaign emails released by WikiLeaks non-stop during the last month of the campaign. The Russian intervention could well have changed the course of U.S. history.

Trump openly applauded this Russian assault on our democracy. That’s bad enough. What we don’t know yet is whether he was involved in secret deals with the Russians, which would be tantamount to treason. But there is still no proof, either, that Nixon personally ordered the Watergate break-in.

As Nixon famously said: “It’s not the crime that gets you … it’s the coverup.”

Trump, who has said that he was thinking about "this Russia thing" when he fired James Comey, is now discovering the truth of those words.

Nixon’s position became untenable after the release on Aug. 5, 1974, of the “smoking gun” tape, in which he said he wanted to use the CIA to pressure the FBI into ending the Watergate investigation. Three days later, Nixon resigned.

The equivalent conversation for Trump became public June 6 when The Washington Postreported that the president had asked his CIA director and director of national intelligence to pressure the FBI to end its investigation into former national security adviser Michael Flynn. Trump also told NBC News that he fired Comey to stop the investigation into the “Russia thing.”

Yet Republicans remain foursquare behind the president. Newt Gingrich, who tried to impeach Bill Clinton for obstruction of justice, now claims, with breathtaking audacity, “Technically the president of the United States cannot obstruct justice.”

Most Republicans were just as willing to excuse the Watergate break-in and coverup, spinning the scandal as a media creation. Sen. Bob Dole, R-Kan., then chairman of the Republican National Committee, opined: “The greatest political scandal of this campaign is the brazen manner in which, without benefit of clergy, The Washington Post has set up housekeeping with the McGovern campaign.”

Republican support for Nixon fell from a high of 90% at the start of the Senate Watergate Committee hearings in 1973 but never dropped below 50% even as his approval among the general public fell to a low of 24%.

Trump also has terrible approval ratings among the public at large (38%) but, like Nixon, he is keeping the support of most of his base — 72% of Republicans still approve of Trump.

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That number is crucial because of the biggest difference between the 1970s and today: Back then, Democrats controlled both houses of Congress, so they could initiate impeachment proceedings with little or no Republican support. Today, Republicans run Congress, and they have shown little enthusiasm for pursuing the Kremlingate probe.

Even if Mueller uncovers convincing evidence that Trump tried to obstruct justice — or if Trump fires Mueller — a sitting president probably can’t be indicted. The only real remedy is impeachment. It’s unlikely, however, that the House would initiate such proceedings unless Democrats win control in 2018. Even then, there is no way to convict in the Senate, which requires 67 votes, without GOP support. As Jonathan Rauch points out, even if Democrats win every Senate race in 2018, they would still have only 56 seats.

In the summer of 1974, a critical mass of Republicans finally decided they could no longer defend Nixon. “There are only so many lies you can take,” Sen. Barry Goldwater of Arizona said on Aug. 6. “And now there has been one too many. Nixon should get his ass out of the White House — today!”

Trump’s fate depends on how many lies today’s Republicans can swallow. So far, there is no indication that they have had their fill, but it’s still early: 447 days elapsed between the appointment of special prosecutor Archibald Cox on May 18, 1973, and Nixon’s resignation on Aug. 8, 1974. We're less than 40 days past May 17, the day Mueller accepted the same role.

Max Boot is a senior fellow at the Council on Foreign Relations and a member of USA Today’s Board of Contributors. Follow him on Twitter @maxboot.

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