How Far Into The Future Should One Care?

I posted a thread last week, eliciting predictions about the far future (2000 years) given what we know has transpired in the recent past and given the pace of scientific and technological advancements. See http://www.nairaland.com/nigeria/topic-150777.0.html.  I was horrified to get the following responses;





Not only did these fail to address the question I had posited, they also revealed a callous disregard for the welfare of generations to come.  That got me wondering whether this attitude was more wide-spread and strongly held amongst members of Nairaland or Africans. 

Basically, how far into the future should we care about the plight of the world?  If your concerns were only restricted to the next few decades, what economic, social, environmental, educational and developmental  policies would you disregard as a result of your limited care and concern?

Case in point:  NASA (National Aeronautics and Space Administration) is currently investing billions of dollars investigating  ways of securing the earth against asteroid impact. Given that such impacts have happen many times in the past and that it is a certainty that it will happen again, is this a worthwhile endeavour?


Are there a class of people who are only concerned about their own short-term welfare and how does this attitude bode  for the construction of a well-balanced and egalitarian society?