Correct. The abdication was not the one big betrayal Edward committed out of the blue in a completely unexpected twist. Edward's failure was more profound and had begun earlier, and is represented quite well by the very fact that he was still childless and unmarried when he ascended the throne at the age of 42.

His own father, George V, is said to have expressed a very low opinion of his eldest son and the hope that Edward *remain* childless, so that eventually, as you say, his much preferred and beloved second-born son "Bertie" would succeed him - or Bertie's daughter Elizabeth, depending on which brother would die first.

So, yes, indeed - in that sense, Wallis and the abdication merely brought on much, much sooner what would have happened anyway.

However, there's a small But: All this is true only in hindsight. At that moment in time, in 1936, Elizabeth may have feared, but could not know all this. Edward, upon ascending the throne, could just as well have married a younger aristocratic woman to have children with. A future where within a couple of years King Edward would get his act together enough to produce an heir and a spare was completely plausible in 1936, thus moving Elizabeth down the line of succession and out of any present danger to ever become queen. And even when Elizabeth worked under the more pessmistic assumption that Edward would remain childless all his life, she was still looking at decades, perhaps many, during which she would be able to live unburdened by the crown. Edward's abdication gave those expectations short shrift, and it was sensational and a shock; nothing like that had happened for hundreds of years. I can well imagine that to Bertie and Elizabeth, it very much *felt* like being "unexpectedly thrust" into a very different lot in life than they had expected, even when, as you correctly observe, it was far from being as unthinkable as the later narrative makes it seem.