In eighth grade, science teachers may have explained to their students that the world would end when the sun expanded to such a size that it would explode, destroying all the planets in its vicinity. Of course, more knowledgeable folks (http://wiki.answers.com/Q/When_will_our_sun_explode and http://answers.yahoo.com/question/index?qid=20080129174949AAJEYmH) have commented that the sun actually will not explode but will bulge out and essentially "melt" the earth... (although perhaps by then scientists may have discovered a way for living creatures to withstand the heat, or we will all have already annihilated each other through nuclear war or fallen to our demise through some other catastrophe).

In terms of "Judgment Day" -- there have been numerous predictions in the past that have not come true. Back in May, news channels focused on "May 21st" as the date for the end of the world (see http://www.csmonitor.com/Science/2011/0518/Judgment-Day-May-21-When-will-the-world-actually-end). Other failed predictions include October 22, 1844; 1806; December 21, 1954; 2000; October and November 1982 (http://www.csmonitor.com/Science/2011/0518/Judgment-Day-Five-failed-end-of-the-world-predictions/October-22-1844).   

Many have also been waiting for the world to end in 2012 (see: http://abcnews.go.com/International/story?id=5301284&page=1) -- as attributed to Nostradamus (http://www.december2012endofworld.com/nostradamus-2012). We still have over a year to observe whether this will happen, or whether something will happen sooner or later. At this point, that's the best answer we can offer -- the world will end... sooner or later.

A vicious cycle like this is perpetuated by traps such as the Prisoner's Dilemma and No-Win Situations. Ideally, resources could be allocated in a way for everyone to come out a winner. However, given the current global political climate and lessons learned from history, humanity is a long way from not wasting resources. Let's just chalk it up to more lessons to be learned...

According to Maslow's hierarchy of needs, we need to meet our own (family) needs before we can begin thinking about meeting the needs of humanity:

Reference: http://en.wikipedia.org/wiki/Maslow's_hierarchy_of_needs
"Maslow's hierarchy of needs is often portrayed in the shape of a pyramid, with the largest and most fundamental levels of needs at the bottom, and the need for self-actualization at the top.

The most fundamental and basic four layers of the pyramid contain what Maslow called "deficiency needs" or "d-needs": esteem, friendship and love, security, and physical needs. With the exception of the most fundamental (physiological) needs, if these "deficiency needs" are not met, the body gives no physical indication but the individual feels anxious and tense. Maslow's theory suggests that the most basic level of needs must be met before the individual will strongly desire (or focus motivation upon) the secondary or higher level needs. Maslow also coined the term Metamotivation to describe the motivation of people who go beyond the scope of the basic needs and strive for constant betterment.  Metamotivated people are driven by B-needs (Being Needs), instead of deficiency needs (D-Needs)." Read more