Actually, the two longest expansions in US history came in the 1960s (Kennedy, Johnson, and early-Nixon) and the 1990s (Clinton).  World War II is a bit of an odd case, though you're right that the economy did grow rapidly during it.  Part of that is due to the full employment that inevitably resulted from massive spending and a contraction in the labor market due to people going over to Europe and the South-Pacific to fight in such large numbers.

The economy was fairly strong during the Truman and Eisenhower eras, but nowhere near the expansion of the 1960s.

Conservatives want live babies so they can raise them to be dead soldiers. - George Carlin