Once the Lilliputians tie Gulliver up there will be no way for Gulliver to communicate anything to them they do not want to hear.
Once the temples, both Roman and Jewish, sandbag Jesus, then Jesus will have no way of saving the Jews or the Romans (other than sheer magic: which is not what Jesus represents). The Romans will see even less well than the Jews that salvation is what was offered: offered and refused!
Once the US jails Crazy Horse while stealing his people’s land then Crazy Horse will be unable to model defense, to demonstrate bravery.
What makes the US invulnerable to salvation is the same thing I started off saying about the Lilliputians: nothing can be communicated to them that they do not want to hear. Once dishonesty is the standard choice, honesty can’t gain a majority. And the Lilliputians will think they are honest: just as the wicked queen still thinks she’s the fairest. Just as kleptocrats believe that all their crimes add up to “good”.
Christians are identical in that respect: so long as they interpret the evidence then there’s no such (rational) thing as evidence. “David Copperfield” determines the evidence, the audience with its wicked queen mirror is the final authority: forgetting one thing: truth is truth, bribes are temporary.
I see Christianity as being as immune to reason as Christians are immune to thinking through their monotheism: God will judge. That is the God of Truth will be the last god standing.