THere are several problems:

First, we have no proof at all extra-terrestrial creatures are there, somewhere in space. So, it doesn't really concern the world.

Second: there is no destination in space (except the ISS but it's no city) contrary to the aviation industry which grew because there always was a destination for the planes.

Third: aviation benefitted from two world wars.

Fourth: planet Mars isn't as hospitable as one might think

Fith: our own planet has much more hospitable places (than Mars) which are not yet permanently inhabited, like the oceans or the poles.

However, until 1987, space had only been occasionally inhabited and since, except for a few months in 1989 and from 1999 to 2000, there always were as at least two humans in space. But this went largely unnoticed.