And an acquitted Trump will be an immunized Trump. Is it vexing to hear Trump’s team misrepresent Robert Mueller’s report as an “exoneration”? Imagine what they will say and do if they defeat impeachment on a party-line Senate vote. It was all fake news, a plot by the Deep State. As false and wrong as those claims will be, how will Democrats sustain the momentum to hold Trump to account after a trial and acquittal? Won’t they then have to submit to the jeers of Trump henchpersons: This issue was litigated, and it’s time to move on?

Impeachment now threatens to turn the 2020 election into a referendum on the Democrats’ methods in Congress, not Trump’s wrongdoing in the presidency, in the campaign, and in private life.

Trump accountability is not an all-or-nothing choice. It’s not now or never. The House can investigate every Trump misdeed, exposing to the light of day everything from allegations of money laundering and bank fraud to the abuse of undocumented-immigrant laborers at Trump-owned properties. It can investigate the Trump-Russia file, not as a case of criminal conspiracy, but as a national-security threat. It can fight the battle for proper Trump financial disclosure in the courts—and summon the national-security professionals who were overruled by Trump when they denied Jared Kushner a security clearance to testify before committees.