WASHINGTON — When the history books are written about this day, they will surely record it as the culmination of a monumental three-year political battle that tested American democracy and delivered victory to an enraged and enraging president over his relentless foes. But they will not record it as the end of the struggle.

President Trump’s acquittal on Wednesday after a fiery three-week Senate impeachment trial provided him a moment of triumph, a sense of validation, a shot of momentum — anything but the finality that he might want. The president who vowed to bring an end to endless wars overseas remains at the center of an endless war at home, one that now moves to the campaign trail and will not be resolved until November at the earliest.

Rather than reaching out to bind the wounds, as President Bill Clinton did after his own Senate impeachment trial in 1999, Mr. Trump made clear minutes after the final roll call that he planned to go on the offensive. He opted to wait until Thursday to make a public appearance, on the advice of aides concerned about complicating the lives of Republicans who cast tough votes for him, but his Twitter feed and staff statements taunted his opponents and boasted of the “Country’s VICTORY on the Impeachment Hoax!”