Allegations like these are of particular interest because of their potential to impact our tribal instincts. My conservative Marine friends place their membership in the Marines very high in their bundle of tribal identifications. When people like Mattis and Kelly--both highly respected Marines--start to question Trump, that starts forces a reckoning between their tribal instincts. Mattis is already on record opposing Trump. That's a pretty big deal.
Kelly has so far been rather circumspect. If he confirms what his friend told these reporters about Trump's callousness to him at his son's grave on Memorial Day, that will be another chink in the armor. If there is confirmation of the disrespect to Marines at Belleau Wood, that, too, could cause a pretty big stir.
I think I said above (somewhere--gawd, this is a long thread) that one of my curiosities about Trump is his remarkably consistent support. 38-43%, plus the margin of error; no matter what is happening and what he's done. This stands in contrast to every President who came before him, who saw their approval ratings sway wildly depending on what was going on and what they were doing. It isn't especially remarkable that a President with negative approval ratings has a chance at reelection: Obama and W both succeeded despite poor polling before the election. And Obama--much like Trump--pursued a reelection strategy surgically focused on getting reelected, not winning the popular vote (though he did win both).
What is remarkable is that no matter what Trump does, he keeps the same level of support. So the question I have from articles like the Atlantic's (and the other media organizations who say they have confirmed aspects of that article) is whether it impacts that support. It won't impact it a lot, but as LH320 points out (I think it was him), this election will be decided by small changes in voters' attitudes, not big ones.
So--does this report lead to military/veterans questioning their past support for Trump? Will one of my buddies, a proud "deplorable," and former Marine--question his allegiance to Trump over this? His reaction right now will be the same as many on this thread: anonymous = fake news. But what if Kelly goes on the record? What if others do? It probably won't change his mind, but it might make him reconsider which tribe is more important to him. It might.
And if it does, that's one of those small changes in voter attitudes that could matter come November 3.
[To be clear, I am not "worried" in the sense that LH320 is rather bellicose about, but I am a realist. I think Biden wins, and I think it's not razor thin--though that's in the eye of the beholder--but I look at the polling, which I trust, and see that Trump absolutely has a non-trivial chance, even if the polling numbers stay exactly as they are now up to election day.]