Julia was thinking about how this man could get everything so terribly wrong. Right at the moment when he answered her, telling her that he would 'treasure' the tapes, she looks at him with a facial expression of surprise:
"Ehm... trea-sure?" she asks him... "... that's actually not what I asked for." she laughs and shakes her head: "... I want the tapes to... disappear. Become... non-existent. Not... put into a box like a treasure to be taken out and used whenever convenient or when you want to look at your treasures!" she is somewhat amused by the fact that they are seemingly talking different things - and not for the first time. "... Oh dear..." she sighs in an exaggerated, yet funny way with a wide smirk. Communication can be a real challenge sometimes, she realizes.
"Let's..." she keeps on the first topic of the tapes... "... let's finish one thing, alright?" and she does not get into the Delta conflict before settling the other topic first.