It's true that the bomber offensive was thought to be a good idea at the time, in part in hope of avoiding the horrendous losses suffered in the trench warfare twenty years earlier.
In the 'unforeseen circumstances' stakes, this failed in two different ways:
(1) the losses we equally, if not more, horrendous than those of the WW1 trenches, and
(2) probably more important in the long run, and more tragic for the UK and Commonwealth countries involved, it wiped out, not just such large numbers of one generation, but the very best of that generation - the potential future leaders of those countries.
You only have to look at the political and business leadership in those countries after the war and to this day to see the stark truth in point (2).