Oh oh! I remember this technique from Cialdini's Influence. During the Korean war, the Chinese used the same technique on American POWs:
For instance, prisoners were frequently asked to make statements so
mildly anti-American or pro-Communist as to seem inconsequential
(“The United States is not perfect.” “In a Communist country, unemployment is not a problem.”). But once these minor requests were
complied with, the men found themselves pushed to submit to related
yet more substantive requests. A man who had just agreed with his
Chinese interrogator that the United States is not perfect might then be
asked to indicate some of the ways in which he thought this was the
case. Once he had so explained himself, he might be asked to make a
list of these “problems with America” and to sign his name to it. Later
he might be asked to read his list in a discussion group with other
prisoners. “After all, it’s what you really believe, isn’t it?” Still later he
might be asked to write an essay expanding on his list and discussing
these problems in greater detail.
For instance, prisoners were frequently asked to make statements so mildly anti-American or pro-Communist as to seem inconsequential (“The United States is not perfect.” “In a Communist country, unemployment is not a problem.”). But once these minor requests were complied with, the men found themselves pushed to submit to related yet more substantive requests. A man who had just agreed with his Chinese interrogator that the United States is not perfect might then be asked to indicate some of the ways in which he thought this was the case. Once he had so explained himself, he might be asked to make a list of these “problems with America” and to sign his name to it. Later he might be asked to read his list in a discussion group with other prisoners. “After all, it’s what you really believe, isn’t it?” Still later he might be asked to write an essay expanding on his list and discussing these problems in greater detail.