ISAAC ASIMOVAssuming we haven't destroyed ourselves in a nuclear war, there will be 8-10 billion of us on this planet—and widespread hunger. These troubles can be traced back to President Ronald Reagan who smiled and waved too much. GREGORY BENFORD YOUR FUTURE AND WELCOME TO IT … 25 years from now. World population stands at nearly 8 billion. The Dow-Jones Industrial Average stands at 8,400, but the dollar is worth a third of today's. Oil is running out, but shale-extracted oil is getting cheaper. The real shortage in much of the world is…water. Most Americans are barely literate, think in...