Cancer, hunger and the like are unlikely to kill the entire human race in one go. A climate event or asteroid could, which would render all other efforts redundant. Mars exploration means hedging the survival of our species.
A diverse portfolio is where the smart money is.
Also, who should determine how the resources of humanity are deployed?
People who arbitrarily have gained control of the resources?
For a tiny fraction of what is spent on space, we could solve world hunger and water.
It also seems a well fed and hydrated global population would be much happier, healthier, creative and productive.
Another question for folks who make the hedging argument — at what point do we say “ok, we have X% of the population living off world, so now we are going to divert funds to make sure people have access to basic human needs on earth.”
You bring up fair questions, but questions that are likely to always be there and never answered. At the end of the day, if we become extinct, all these questions are superfluous anyway.
Space exploration is, quite literally, a moon shot. But it's one that could give us the space (pun intended) to keep trying to solving the rest of the issues.
No we realistically can't. How exactly do you propose doing that? Keep in mind that there is a ton of precedents where local governments withheld foreign aid (which was supposed to "solve hunger" at least at that part of the world) to enrich themselves and/or to control their citizens. How do you solve that with any amount of money? Bomb the "bad governments" into submission? Just keep the money in some account waiting for those governments to become more civilized? Might as well colonize Mars in the meantime
Surely, if a NYC nightclub promoter can stop doing blow and start drilling wells, we can scale what he is doing.
- water access is a source for income in quite a few places (e.g. [1]). Drilling a few wells in remote villages might fly under the radar, but "solving clean water" means cutting people very much capable of violence from their income. That can't be solved by NYC nightclub promoter, unless they are willing to wage urban warfare.
- it's not enough to drill the wells as they will dry out eventually if there are no regulations and water distribution infrastructure. It's just not sustainable. And to solve the water problem sustainably requires a lot of infrastructure, water treatment, pipes, pumps, maybe some desalination plants. Even US itself is too gridlocked to solve its own problem of water supply, allocation, and aging infrastructure (e.g. Flint or CA's almond orchards), despite having all the money in the world. Why do you assume it's somehow enough to throw a few trillions at a few dozen countries with wildly different political and cultural climates?
[1]: https://www.bloomberg.com/news/features/2018-06-25/thirsty-v...
Is a humanity that doesn’t bother taking care of its own people worth saving?