Here is an interesting letter by Ernst Stuhlinger, then an associate director of science at NASA's MSFC, written to a nun in the 1970s. He explains the crucial role of space exploration in a country's growth. This topic sparked some engaging conversations on HN in 2012 and 2015:
Anyone who thinks India doesn't need a Mars mission, please raise your hands up.
Done, good. Now you've given your opinion. Please sit down and shut the F up.
Whatever I write would pail in comparison to a thread posted a few days earlier:
Link: http://launiusr.wordpress.com/2012/02/08/why-explore-space-a...
HN discussion: http://news.ycombinator.com/item?id=4372563