If I had the energy, I'd also pull out a bunch of refs on the topic of "affairs are a national security risk because of blackmail."
I'm a bit tired, but whistlestop tour.
There are indeed occasions when affairs can be a national security risk because of blackmail.
Trump is unusual because he's SOOOO vulnerable in this respect. We now have evidence of him being vulnerable actually during the time of the election as well as afterwards. National Enquirer did a "catch and kill" of the Stormy Daniels cover-up, some details below but IIRC Trump and Cohen also discussed their concerns that NE's David Pecker would retire or sell the magazine, and the need to further secure the story if this happened.
www.theguardian.com/us-news/2018/dec/12/national-enquirer-trump-payments-david-pecker-catch-and-kill
Fox News also sat on one of the affair stories before the election.
So Trump was already deeply in hock before he was sworn in.
Oh, um, pee-pee tapes. If true, or even half-true, then he was much more deeply compromised and by a foreign power.
More on the topic of being compromised...
Sally Yates made clear in her evidence to the Senate Judiciary Committee in 2017 that Michael Flynn was compromised and blackmailable by the Russians, and that she'd informed the White House of this, and that they didn't seem at all bothered. Flynn was convicted of lying to the FBI; he'll be sentenced on 28 Jan 2020, so date for diaries.
IIRC, although Yates assumed at the time that Mike Pence had been misled by Flynn, there's still the possibility that Pence wasn't misled and did actually know that Flynn had been offering official US sanction-relief to the Russian ambassador while Flynn was just a private citizen and Obama was still president. Might still be some shoes to drop there. Have to wait and see.
en.wikipedia.org/wiki/Michael_Flynn