This. This is such an important red flag in the book. There is also a passage (earlier, I believe) where — if memory serves me right — he and Usha are visiting DC, and something causes him to stonewall her. As in, he just walks away from her after some kind of disagreement, going for a very, very long walk across the city, and she trails him from a distance because she's panicked about his mental state and whether he might hurt himself. When she finally catches up to him, she demands that he SPEAK to her to resolve disagreements in the future, rather than doing anything like that again.

Stonewalling is emotionally and psychologically abusive. One partner shouldn't have to beg the other to resolve disagreements in an adult fashion.

This is not to say that abusive people can't heal or outgrow their emotional dysregulation, but the "I can be defused" / "Usha has learned how to manage me" bit implies that he did not heal or outgrow this kind of behavior yet. It's troubling, and it shouldn't be a personality trait of a man in charge of a country.