A Certain Slant of Light

Le Carré is not pulling any punches! We are going to drill right down to what "things he regrets" and "moral compromises" look like from the point of view of the people who ended up dying of those regretted moral compromises. And not just dying! Dying realizing that they have achieved the opposite of their own personal goal, and were in fact SET UP to achieve that result by their own service which they trusted!

And even if Leamas did make it back alive, what would the rest of his life look like? He's torched his whole life for this mission, and he can't just tell everyone "Yeah, it was an elaborate double-cross," because that would undermine the whole mission! (Which at this point he probably wants to do, but I can't imagine he'd be able to get away with it...) Whole life down the drain and Liz dead to save fucking Mundt.