Totalitarian systems of opposite ideologies converge in method: both the Nazi and Soviet states demand that the individual dissolve into the collective, and both treat the deliberate killing of innocents as administrative routine. The symmetry suggests the decisive variable is the total concentration of power, not the content of the creed it serves.
Senseless, unwitnessed small acts of kindness, an old woman handing bread to a captured enemy soldier she has reason to hate, persist even where every organized ideology of good has been turned into an instrument of murder. This 'senseless kindness' is treated as more durable than any doctrine precisely because it is private, spontaneous, and serves no system.
Every doctrine that claims to serve a universal future good licenses present cruelty in proportion to the size of the good it promises; the grander the collective ideal, the more individual suffering it can justify as necessary. Freedom and human decency therefore survive only in the particular, concrete person, not in the abstract cause.
The physicist Viktor Shtrum, having made a major discovery, is ostracized and expects arrest during an anti-Semitic campaign, then is suddenly rehabilitated when Stalin personally telephones him. Relieved and grateful, he is soon pressured to sign a letter denouncing innocent colleagues, and he signs, discovering that reprieve and success corrupt resistance more effectively than terror.