Trump will debate Harris September 10th on ABC.
Will he, though?
That's a month out, and as we're learning, a month can be an eternity in this campaign season. A month ago, it was a foregone conclusion that Trump was on a roll. Polls were all in his favor. Biden was a disaster. Over the last week or so, the polls have flipped in favor of Harris/Walz. Not in an "if the election were held today it would be a landslide" way, but the Trump camp is currently back on their heels.
The Democratic ticket is barnstorming across multiple swing states this week (PA, MI, AZ) while the Trump campaign is headed to....Bozeman Montana.
The question remains if the Trump camp can find a line on Harris/Walz and land some blows. I'd say that's unlikely, but again...it's another month until the (maybe) next debate. As for the debate itself, a lot hinges on the rules that the host(s) lay out. If Trump is allowed to stalk the stage and shout over his opponent like he did with Hillary in 2016, it might be a wash, since Harris hasn't been especially strong in this area.
That is, if he even shows up. He seems to be leaning towards an "if I don't have an audience I can feed off of, I'm out" stance, but then, that didn't hurt him against Biden.