I believe that once upon a deluded time they said that 'the bomber will always get through', which was of course nonsense, but cheered and scared in equal measure depending on whose bombers you were thinking about.
I have similar feelings about the 'cruise missile will always get through' school of thought. I don't buy it for a second. Some might, but to which locations? The heavily defended ones? Which tend (uncannily) to be where the baddies put their valuable stuff - I doubt it. Sure they did in previous conflicts and sure they will have a role to play in the future. But against high capability IADS I think that whilst they do have utility their day - of impervious attack of the high value list - might have been and gone.
Others will, naturally, disagree.