Capitol Hill hadn't seen this potential for an explosive confrontation by a president in 21 years. Not since former President Bill Clinton addressed a joint session of Congress in 1999 had a president delivered a State of the Union speech during a Senate impeachment trial. Clinton chose at that time to avoid the topic completely, instead offering a traditional address focusing on his agenda and the accomplishments of his presidency over the previous year.

President Trump, however, is anything but traditional, with a reputation for undisciplined public declarations and a strong impulse for retribution. Ever since his impeachment, Trump has railed on Twitter and in his rallies against House Democrats in general and Speaker Nancy Pelosi (D-Calif.) in particular, who would have to sit quietly behind Trump regardless of what he said in his speech. The event had the potential for, if not an Oliver Cromwell-esque moment, then certainly a historical presidential dressing-down of Trump's nemeses.

Instead, Trump offered what may have been his most surprising performance yet. Trump gave a conventional State of the Union speech, offered it in a disciplined and effective manner, and never once even hinted at impeachment.

That isn't to say that Trump and Pelosi didn't have their moments of pettiness. Pelosi offered her hand to Trump when he approached the dais with her copy of the speech, but Trump ignored it and turned his back on her. Pelosi offered her own symbolic rejection of Trump by tearing up his speech at the end and throwing it into the trash, with neither offering the other a handshake as Trump finished the speech.

Otherwise, the most remarkable aspect of Trump's State of the Union speech was how it focused entirely on, well … the state of the Union rather than on himself. To be sure, Trump started out with a laundry list of accomplishments by his administration, but that is the normal form for these speeches. Trump also listed out his policy goals for the upcoming year — really more of a campaign agenda — but again, this is the convention for State of the Union addresses. So too are the touching personal stories of the president's guests, who are invited to highlight specific policy issues and legislative demands. That they did with significant emotional impact, on which presidents have long relied to pressure Congresses to bend to their legislative will.

Surprisingly, Trump refrained from even a mention of impeachment. That possibility had worried some Senate Republicans who fretted that he could upset the delicate balance of negotiations that has taken Senate Majority Leader Mitch McConnell (R-Ky.) all the way through to a slam-dunk majority for acquittal. Nor did he attack the Bidens, or even talk about his presidential campaign. He stuck to the script, kept his discipline, and finished out his speech in a conventional and personal finale on the spirit of America and the greatness of the country. "The best is yet to come," he concluded.

At any other time, perhaps a conventional State of the Union address would simply speak for itself. For this moment, though, it has a greater strategic value than just the normal efforts to push a legislative agenda. Trump's speech delivered a response to impeachment on a completely different level — and on the House Democrats' turf, no less.

Key to the impeachment push that has percolated for the last three years among Pelosi's caucus is the argument that Donald Trump is a dangerous man. Rep. Adam Schiff (D-Calif.) argued in his closing to the Senate that Trump might be so emboldened by an acquittal to attempt to sell Alaska back to the Russians or let Jared Kushner declare war. Impeachment managers accused Trump of presumptions of dictatorship, pretensions to royalty, treason, bribery, and a host of other accusations of lack of control. They pressed the case even knowing that it had no chance at all of winning 67 votes for removal in order to underscore Trump's alleged abnormalcy and the danger he poses to the Republic.

Rather than fulfill those predictions with a rant on the House floor during the joint session, Trump's speech offers an answer of its own. Trump could have taken the bait and turned this speech into a rebuttal to the two weeks of argument that has been carried non-stop by television networks. Instead, Trump put his presidential mien on stage for this occasion, rising above that version of partisan bickering to focus more on the usual partisan bickering over policies that American voters want addressed. Look how normal I actually am, this speech and its delivery communicate to voters who tuned in expecting a Trumpian wrestling match or campaign rally.

Trump and the White House clearly have to hope that these same voters who watched both the trial and the State of the Union see the contrast between the man House Democrats have described and the one voters can see for themselves. If Trump can stick to this discipline, it will paint Schiff and his fellow managers as the actual agitators, the people who broke the norms to overturn an election to get rid of a president they just don't like.

Maintaining that discipline will be tough for Trump, whose natural impulse is to strike back against any criticism, but this strategy of focusing on embracing conventions may already be paying off. A new Gallup poll out this week shows Trump hitting the highest job approval mark of his presidency (49 percent) as he ramps up his election campaign. The GOP appears to be benefiting from this change too, as they are now viewed more favorably (51 percent) than at any time since April 2005. Democrats' favorability dropped slightly from 48 percent to 45 percent since September, before the impeachment effort began. And most significantly, registered voters are split 50/50 on whether Trump deserves re-election — a vast improvement from the 41/56 Trump got when Gallup last asked the question just prior to the 2018 midterms.

Trump will never be a completely conventional president, and his voters would be disappointed if he became one. All he needs to do to win re-election is to convince everyone else that he knows when to be conventional and when he can afford to be a strategic chaos agent. Trump succeeded in drawing that contrast to the accusations of House Democrats during his State of the Union, but he'll have to keep it up for the next nine months to make it stick.

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