Allan J. Lichtman

To impeach or not to impeach, that is the question: If the president’s misdeeds are serious, not minor or technical, then the answer is yes. As students of history, the framers knew that power corrupts, and they established impeachment as a legal and peaceful means for escaping tyranny without having to resort to revolution or assassination.

Recognizing that presidential misdeeds can take many forms, the delegates set the criteria for impeachment and removal broadly, trusting in the judgment of America’s elected representatives. The resignation of Richard Nixon, who was faced with the prospects of impeachment and conviction, removed from office a president who threatened America’s constitutional order and likely had committed treason and crimes against humanity in Southeast Asia.

President Trump need not match the level of misdeeds of Nixon to warrant his impeachment. But Americans should be mindful of the distinction between that which merits punishment and that which is merely a matter of preference. For example, Trump’s unconventional style or his lack of “presidential” stature and demeanor might offend, but those are not offenses worthy of impeachment. Differences of policy and values do not make a case for impeachment, either. If Trump listens, he can yet change his ways.

Even so, Trump’s history and the path he has followed — as candidate, president-elect and president — show that he is uniquely vulnerable to impeachment. It took three years for the House to impeach Andrew Johnson and nearly five years for the impeachment of Bill Clinton and the near impeachment of Nixon. Yet in the early stages of his presidency, Trump has already begun matching the abuses of Nixon.

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Is it shouting into the wind to make the case to a Republican Congress for impeaching a president of their own party? The answer is no. Once Trump becomes more of a liability than an asset to the GOP, the party may be willing to turn on him through impeachment.

Circumstances for Republicans today are far from those of 1868, when the controversial and polarizing Benjamin Wade would have become president in the event of Andrew Johnson’s removal. If the Senate removes Trump from office, then Vice President Pence, a Republican dream president with experience in Congress, rises to the White House.

As always in politics, complications lurk within every scenario. By supporting the impeachment of their president, Republicans will turn the very dangerous Trump into their enemy, which could have nightmarish consequences if he survives conviction in the Senate. They would risk the alienation of his loyal followers and the potential loss of dozens of House and Senate seats in the midterm elections of 2018.

Still, if Democrats solidly backed impeachment, only some two dozen House Republicans would have to join the Democrats for a voting majority. When the House Judiciary Committee took a vote on articles of impeachment against Nixon, it revealed that egregious transgressions can crack party loyalty; six of the committee’s 17 Republicans joined all 21 Democrats in backing two of the three articles that the committee endorsed.

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Democrats would also be wise to think now about what they wish for when faced with the prospect of a Pence administration in the event of Trump’s impeachment and removal. Yet despite sharp policy differences, Democrats could likely trust Pence as president to respect the Constitution and the law, stand firm against Russian aggression, and not risk a nuclear war.

Former lawyers in the Obama administration have formed a working group to monitor violations of the law and the Constitution by Trump. But the fate of Trump will ultimately rest with the democratic activism of the American people. Americans rightly celebrate their nation’s Founders: Thomas Jefferson for justifying independence; Washington for leading the Continental army to victory in the American Revolution. But it was the protests of ordinary colonials, men and women, whites and blacks, that turned public sentiment against King George III and ignited the revolution. “The Revolution was,” as John Adams wrote, “in the minds and hearts of the people.”

The many robust demonstrations against Trump will be like smoke through a chimney unless, like the revolutionary protests, they are put to a purposeful end. If investigations uncover traitorous collusion with the Russians or Trump continues to clash with the law, the Constitution, the environment, and the nation’s traditions and its security, the American people must demand his impeachment. If Republicans in Congress remain recalcitrant, voters should be swift to dismiss them from office in 2018. Justice will be realized in today’s America not through revolution, but by the Constitution’s peaceful remedy of impeachment — but only if the people demand it.

Allan J. Lichtman, a distinguished professor of history at American University, last year correctly predicted Donald Trump’s victory based on his bookThe Keys to the White House. This column is excerpted from his new book The Case for Impeachment, published today.

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