Nancy Gibbs is the director of the Shorenstein Center on Media, Politics and Public Policy at Harvard’s Kennedy School of Government.

It’s hard to bar Donald Trump from running for president again, but it may be possible to discourage him.

If the Senate fails to convict Trump for incitement of the Capitol riot, a rare convergence of principle and ambition can effectively disqualify him from ever running again and broadly serve the common good.

The principle holds that leaders must preserve and protect democracy whether it serves their personal interest or not.

The ambition belongs to Republican senators looking to clear the 2024 field for themselves.

The process starts by hardening norms into laws. Once presidential candidates become their party’s nominee, they should be required to release their tax returns to the Federal Election Commission or some bipartisan body that can look them over. You can argue over how many years of returns — five seems reasonable — but no hiding behind claims of privacy or audits. Sen. Ron Wyden (D-Ore.) has a bill that would make this law; Congress should adopt it. Using the right to privacy to hide one’s history as a grifter seems like a protection we can no longer afford.

Also: Have you done business with folks overseas? We need the details. Are you in debt? We need to know what you owe to whom. And if yours is a family business, your kinfolk warrant an extra measure of scrutiny as well. It is counterintuitive to work to preserve democracy if that means putting on blinders about a potential commander in chief’s financial relationships overseas or at home.

The convention that presidents divest their commercial interests or place them in a black box needs to be clarified and codified. Handing the keys to the kids doesn’t count. The presidency provides those who hold the office plenty of ways to get rich once they leave. But using the office as a real-time ATM is wrong, far too tempting to people of a certain bent and, above all, a security threat, as Trump’s servility toward a variety of foreign countries testifies.

Next, ethics rules can’t be considered optional. The 1939 Hatch Act, designed “to prevent pernicious political activities,” prohibits federal employees from engaging in political activities or using government property for political purposes. “Nobody outside the Beltway really cares,” declared Trump’s last chief of staff,Mark Meadows,, whose White House violated the act practically on a daily basis.

Maybe not, but the agents of accountability, from inspectors general to career prosecutors to agency whistleblowers, now need to be rearmed in light of Trump’s willful (and easy) defiance of them. The framers of the Constitution knew we would need checks and balances on personal greed and lust for power; James Madison argued in Federalist 51 that “ambition must be made to counteract ambition.” We’ve let our guards down. Raise them up again. It should be possible to preserve legitimate presidential prerogatives without enabling autocracy.

How do we make it harder to populate a government with lackeys whose greatest loyalty is to a person and not the public? Back in 1960, when President-elect John F. Kennedy picked his brother Robert to be attorney general, the youngest since 1814, Sen. Hugh Scott (R-Pa.) called the nomination “a little bit ominous.” In 1967, Congress passed a federal anti-nepotism law, and Presidents Richard M. Nixon, Jimmy Carter, Ronald Reagan and Barack Obama were all blocked from appointing relatives even to advisory committees.

But on the day of Trump’s inauguration in 2017, the Justice Department ruled that presidents aren’t bound by those rules when it comes to White House appointments, only jobs at “executive agencies.” Congress should revisit these definitions. Presidents have often depended on their relatives for advice; that should not entitle next of kin to a salary, a security clearance or a role they can leverage for their own purposes.

Congress may think it dodged the worst of Trump and Trumpism when lawmakers at the Capitol fled on Jan. 6 just ahead of a mob. But democracy will not recover without some long-neglected reforms. If it seems a fantasy that a microscopic Democratic majority could harden democracy’s defenses, these strange circumstances may yield a coalition of the willing. Senate Republicans — even members of the Sedition Caucus — could fulfill their promise to drain the swamp if those reforms also repel any future candidates whose last name is Trump.

It runs deep in American mythology that anyone can grow up to be president. We take that as a blessing; but now that we know the kind of person we are capable of electing, it should be a warning as well.

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