8. The 2016 precedent. Finally, President Trump’s offense here was, at most, to leverage his power to advance his political ambitions — in a manner that was minor, temporary, and without effect. It does not hold a candle to what Democrats did in 2016, when the incumbent administration placed the intelligence and law-enforcement apparatus of the government in the service of the Democrats’ agenda to win the election and, failing that, to suffocate Donald Trump’s administration — an enterprise that energetically exploited the Obama administration’s conduct of foreign relations. Tellingly, Democrats oppose any investigation of that scheme, let alone accountability or impeachment for any participant.

The president and his supporters are wont to say that the Democrats’ exploitation of presidential powers for partisan political purposes is the worst abuse of power since Watergate. If it is proved, it may well be — we’ll have to see what the Justice Department’s investigations establish. For myself, though, I don’t see how one can condemn what happened in 2016, yet not see any problem whatsoever with President Trump’s handling of Ukraine — even with the caveat that to portray the Ukraine excesses as grist for impeachment is overkill.

That caveat is the president’s best foot forward in opposing impeachment. It is also the best reason why Democrats should stand down. Ukraine seems like an effective campaign issue for them, especially if Joe Biden is not the nominee. As the basis for putting the country through an impeachment crisis, though, it is likely to explode on them.