Just posted in the “Expert Voices” section of Science magazine (26 Mar, vol. 391 #6792):
https://www.science.org/doi/10.1126/science.aef4989
Andy Lawrence, Is astronomy a luxury? 10.1126/science.aef4989
Astronomy includes planetary defense, and is therefore not a luxury. The cost of planetary defense telescopes has been analyzed to be well worth it- that is, the damages from asteroid impact clearly justify the (rather small) amount we spend on glass.