Avi k
you are mixing issues
RMF halachically [!] disagreed with those who assered giving back land even bimkom pikuach nefesh . nothing to do with the principle of datt torah
there was no ‘psak’ by r ch’o about shanghai at any time
by the way rch’o was niftar just weeks after the soviets marched into vilna
before the yeshiva moved from lithuania
daat torah was never invented
it exists only to the extent that there are sources in the torah supporting it
and cannot be an invention if thereare sources for it
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