There's no reason we can't do both. Claiming money spent on researching/development of XYZ should take a backseat to some other problem is extremely short sighted.

For example, sattelites not only help us understand climate change, but are actively used to track down methane leaks, CFC leaks and other issues. We can track forest fires by sattelite as well, and fight them more effectively.

The only points where it really makes sense to say "why are we funding X when we should be focussing on Y", is when X is actively detrimental for no real gain. For example, fossil fuel subsidies, meat subsidies, schemes that protect local products to the detriment of other (shipping Dutch pigs to Italy to produce "Parma" ham).

Many reasons actually. You more than likely have something on you and use something daily that only exists due to things implemented for space travel. Those "side products" really add up, since space is so frigging hard on everything, which forces human innovation to go beyond the current limits. That new ground is what fuels innovation, fuels economies, fuels wealth. And that in turn should power things like space travel, since that helps growing the space for innovation even further.

While I could point out obvious stuff like PV-panels or smartphones, how about thermoacoustic refrigeration? Invented for the James-Webb Telescope, they are currently evaluating entire new fields where this cooling method saves lots of power - remarkably, the Telescope was planned with this technology even though it did only exist as an idea at the time, not even as a working prototype. That created lots of jobs and now keeps creating new ones as it opens the field for cooling things to near-absolute zero that are highly sensitive to vibrations. They are still trying to understand the technology, since it works.

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