Jaakko takes the letter and reads.
"So Xiaomei won't talk to anyone? I wonder if something's happened," he wonders out loud.
He then continues on reading and gets to Yui.
"Oh, Gods damnit," he says quietly.
Jaakko, on top of his feelings regarding the airliner, has the despair compounded by guilt. At first for Yui's death, and then some for Roger's. He stares blankly at the letter, remembering Roger throwing his aircraft into the Morgenstern's missile salvo to save him, seeing it again. He begins reasoning with himself that Yui did her job, getting her Thunderbolts to bare against the destroyers before being forced out by a burst missile, and then murdered on the ground. Roger's death is harder to justify, and Jaakko feels like he perhaps owed Roger something more.
He finally shakes himself out of it.
"Did you say something?" he asks Tippy in a quiet voice, a bit confused, believing Tippy had said something while he was zoned out.
To that end he's wrong. Jaakko returns the paper to Tippy.