If you're going to be mind-killed yourself, Vlad, posting endless nitpicking comments here trying to rebut anything anyone says, you should at least be more precise in your demands, because it is trivial to find attempts, even despite all secrecy and faded memories.

I am disputing your very central claim, so even if I am wrong, I don't see how this can possibly constitute "nitpicking." If it was in fact reasonable in 1939 to consider the possibility of a British plot to assassinate Hitler as wildly implausible, your original points don't stand at all.

And indeed, I do believe that government-orchestrated assassination plots against a head of a foreign state were indeed considered a wholly separate category of wrongdoing back then, and one that was a particular taboo. You just can't put other sorts of assassinations in the same reference class.

If you insist that things like the assassinations during the sectarian struggles in Ireland fall into the same reference class, then the inferential distances may really be too large for us to have a productive discussion here. But still note that you won't find any examples of the particular sort I asked for. (Except arguably for the killing of Dollfuss, something that it actually took the Nazis to do.)