It's graceless and ugly, and rarely a good idea, to kick people when they're down.
The word "triumphalism" captures that kind of kicking. In a polarized political environment, triumphalism is dangerous.
Many Republicans are joyfully celebrating the confirmation of Justice Brett Kavanaugh. Texas Sen. John Cornyn tweeted a photograph of what was apparently Champagne, with the words, "Not quite #Beers4Brett but #Bubbly4Brett instead."
Senate Majority Leader Mitch McConnell, R-Ky., says that he wants to “thank” Kavanaugh’s opponents — whom he called “the mob” — because “they’ve done the one thing we were having trouble doing, which was energizing our base.