I cant rule out ENFj as a possibility either, but I dont think ISTj. Tchang kei chek was ISTj and they seem nothing alike though I guess you could argue for two different subtypes.
Yeah, Chiang Kai Shek is most likely ISTj.
Another ISTj politician I can think of is Zhou En Lai:
Maybe it's only me, but I think quite a number of Chinese politicians seem to VI alike, as if they are from the same quadra.