Absent World War II and the development of long-range aircraft it spurred, how might transcontinental, but especially transoceanic travel have developed?
By the mid/late 1930's, a nasty string of crashes had begun to cool ardor for airships, but private industry perhaps lacked the resources to refine and mass-produce long range landplanes without leveraging off WWII R&D.
On the other hand, transatlantic liners had probably begun to reach their limits: in shipbuilding, every additional knot beyond 25 or 30 is exceedingly costly in terms of power required.
that being said, how would travel have developed?