as for the 1929-1955 issue, here's what I wrote earlier - it still stands. that 1920-1955 flatline is a myth - only true for truly bad investors.
You are looking at just the Dow Jones from 1929 to the mid 1950s. I read a great study of that period that showed that the average stock was up in the 7% per year range during that period.
Yes, the Dow stagnated for decades, but that is because 1) the Dow is just 30 monstrously giant stocks 2) the index was manipulated many times - stocks in, stocks out, 3) you were starting at a riduculous bubble time. Money invested through the 1920s even in the Dow recovered by 1943.
(I believe that if they had just left the Dow alone and not changed its composition, it would have recovered much earlier. Remember when those nitwits added Microsoft and Intel to the Dow in Sept 1999? Those stocks are less than half their value today - I'm sure the stocks they kicked out have done far better)
A US stock/bond balanced portflio recovered from the 1929 crash by 1936. Small stocks by 1943. World markets by 1937.
Not great returns, but your assumption of decades of stagnation for stocks is dead wrong. Diversify and prosper, ice cream bar fan."
as for kennedy - first off, was he the richest? hard to find a source, but this implies he was top 20, but not richest. minor point. http://en.wikipedia.org/wiki/Joseph_P._Kennedy,_Sr.#Business_career
second of all, he made his money through business, not by investments.
third of all, interesting choice of millionaires - given that Kennedy also was a conspiracy theorist who thought the US was being dragged into a war (ww2) by the same evil, evil, people you rave about. Any chance you will think your conspiracy theories will be viewed as lame as Joe K's are now?