Anyone wondering whether Donald Trump's live tweeting would distract from Tuesday's vice presidential debate didn't have to wait long for an answer: Yes.

Just as the rhetorical contest between Mike Pence and Tim Kaine was getting underway, Trump conjured the memory of his nasty, one-sided feud with Fox News Channel's Megyn Kelly by sniping at the host on Twitter.

It isn't entirely clear what Trump was responding to, though it appears Kelly was under the impression that Trump campaign manager Kellyanne Conway is among the aides keeping the Republican presidential nominee company during the debate. Those aides reportedly include Steve Bannon, Hope Hicks, Stephen Miller and Dan Scavino — but not Conway, who is with Pence in Farmville, Va.

Trump's Tuesday-night tweet at Kelly is much milder than some he has sent in the past.

Still, it is hard to see the upside in doing anything to remind voters of one of the ugliest episodes of the campaign — especially as Trump tries to combat charges of sexism in the midst of his latest public spat, with former Miss Universe Alicia Machado. And it is hard to understand why Trump would take the spotlight off his running mate and top surrogate on Pence's biggest night of the election.