Growing up in the 1950s, to say something was “on the other side of the world” was synonymous with placing it on the moon: a (cognitive) distance not within normal human experience. It would have taken days to fly commercially on propeller-engine passenger flights to, say, China.
A few summers ago I flew to China from the Mississippi Gulf Coast--in time-zone and international date-line and sun up-sun down-sun up disorientation--in approximately 16 hours, including time watching people in three airports. I cannot estimate, within a thousand miles, how far is China. I can, however, measure it in the time--today--it takes to travel there.
Is China still “on the other side of the world?” In absolute distance it might be 8,000 (?) miles. In temporal distance it is about 16 hours away. In cognitive distance?--the world now has no “other side.” After all, it is now a small world, both in space-time distance and in our spatial cognition.