Feel free to elaborate.

I suspect any reasons you'll come up with are all still less urgent than the needs of our Earth.

I've heard the argument about learning to control the climate through taraforming (or whatever you want to call it), but I'm completely unconvinced that is an efficient method.

I'd be willing to be convinced otherwise, but I'm very skeptical.

Once even a minuscule fraction of the resources of the Solar System become available you can solve all terrestrial problems once and for all.

Space & Solar System is big and has a lot of resources, much much more than what is available in on a terrestrial planet.

There are multiple catastrophic events that could end civilized human life on Earth that we have 0 control over.

Asteroids, supervolcanoes etc.