In 1999, in the midst of his impeachment trial, Bill Clinton delivered a typically verbose State of the Union Address that ran for 78 minutes. Although it surprised many at the time, Clinton did not display a glimmer of concern about his predicament or allude to impeachment in any way.

Even more than most presidents, Clinton had a rare talent to compartmentalize. But the 1999 State of the Union was more than just an artful performance by a political master of denial. At the end of his speech, Clinton actually unveiled a new political argument that shaped the final two years of his presidency.

In 1999, one of the biggest domestic problems facing America was (nostalgia alert) what to do with the coming budget surplus. Anticipating Republican pressure for massive tax cuts, Clinton concocted a devilishly clever response.

In his State of the Union, Clinton said about the surplus, "I say, we shouldn't spend any of it — not any of it — until after Social Security is truly saved. First things first."

That argument gave rise to the Democratic slogan, "Save Social Security First," that prevented any major tax cuts until after George W. Bush was elected in 2000.

Donald Trump — in case somehow you have failed to notice — lacks the ability to compartmentalize.

Trump, in a way, lives up to the famous description of the ousted Bourbon monarchy in France: "They have learned nothing and forgotten nothing." All Trump remembers are the grudges and the hatreds while stubbornly refusing to learn from them. Or even learn that Kansas City is in Missouri.

In theory, on Tuesday night the president should turn into Teleprompter Trump as he turns the other cheek. While I do not empathize with Trump's White House enablers and lackeys, you can just imagine their frantic efforts to convince him to be magnanimous as he delivers the State of the Union.

But Trump also knows that he is at his most boring reading off a teleprompter. And that his hard-core political base (the only people on the planet that the president even pretends to care about) craves red-meat rhetoric.

So the State of the Union invariably will become a high-wire act as legislators in the room and viewers at home wonder whether Trump will throw off the restraints that have constrained all other presidents on formal occasions like the State of the Union.

Will Trump get mad and start snarling at "Shifty Adam Schiff"? Will Trump wheel around and face Nancy Pelosi eye-to-eye and make some crack about how he won and she lost? Will Trump refer to the Salem witch trials more often than Arthur Miller did in his play "The Crucible"?

Unlike Clinton, Trump can never safely take refuge in policy proposals.

It will be hard for the president to brag about his Glorious Wall when the Washington Post reported that key portions of it will have to swing open during summer months to protect the structure against flash floods.

A normal president might use the State of the Union to reassure a jittery nation about preparations against the spread of coronavirus. But Ron Klain, who directed Barack Obama's response to Ebola, pointed out, "The combination of Trump's paranoia toward experienced government officials, inattention to detail, opinionated rejection of science and evidence, and isolationist instincts may prove toxic."

Foreign policy is another tricky area for Trump. This is not exactly the ideal time for the president to brag about the success of his "bromance" with Kim Jong Un. And even an inveterate liar like Trump could not pull off claiming that America is doing everything to help Ukraine resist Vladimir Putin's aggression.

Sure, Trump can brag about the economy and say with characteristic understatement, "The state of the union is better than at any time in human history. It is even better than Adam and Eve had it in the Garden of Eden."

But it is hard to concoct a legislative agenda for 2020 when the only reason for the Senate to stay in session is to rubber-stamp right-wing judges and to refuse to acknowledge the existence of John Bolton.

Unless Trump veers in an unexpected direction (maybe threatening to nuke Denmark unless they hand over Greenland tomorrow), the State of the Union is likely to be a ratings disaster. Especially compared to the genuine drama of caucus night from Iowa and the historic formality of Wednesday's impeachment verdict.

That is why the congressional Democrats should vow to avoid cheap tricks on State of the Union night. No mass walkouts, no angry shouts of "You lie" and no mocking laughter. All the Democrats need to do is to display the mild boredom of an 11-year-old receiving an etiquette lesson from Aunt Sylvia.

If the Democrats are successful in November, this will be Trump's last State of the Union address. Especially since it is hard to picture a defeated and defanged Trump making a pilgrimage to Capitol Hill next January.

As a result, this may well be the last time for voters to draw a visual contrast between Trump and the congressional Democrats. The best way for the Democrats to win Tuesday night's image war is to come across as the party of dignity and restraint — a party that does not make a mockery of America's patriotic traditions.

Trump revels in any moment when he is the center of attention. But the State of the Union may be the rare exception, as Trump becomes a president who stands before the nation with absolutely nothing noteworthy to say.

Walter Shapiro has covered the last 10 presidential campaigns. He is also a fellow at the Brennan Center for Justice at NYU and a lecturer in political science at Yale. Follow him on Twitter: @MrWalterShapiro.