As one who generally admires Q for standing up to anyone, friend or foe, superior or inferior, I really don't like it when he says to Croder, after being told the *real* story of what Schrenk is doing, "If I'd been given this information. . . . I would have eliminated Schrenk the minute I found him." [17:144]
I doubt that is true, because Q *did* know the general outline of Schrenk's plan, it having been revealed to him indirectly in the apartment ("there's only one thing those bastards'll listen to" [14:139]). For Q to pretend that it is the seriousness of what they expect Schrenk to do that determines whether he'll follow Croder's instructions is disingenuous. By the time of the showdown in Schrenk's apartment, Q has been told or has deduced the following: (a) Schrenk could be picked up and made to spill the beans about the Leningrad cell; (b) Schrenk is planning an act of terrorism; and (c) Schrenk is a vengeful instrument of destruction who refuses help. If that isn't enough to justify terminal action, I don't know what is.
In the confrontation with Croder, Q thinks that he doesn't want to say he'd been planning to kill Schrenk anyway, because it would have sound "like a lie." In fact, that sounds less like a lie than blaming his lack on resolve on gaps in Croder's briefing.