>> One of my favorite SF stories ever (though I've forgotten the title or
>> author) involved human beings conquering most of the galaxy after we
>> were invaded by a civilization with roughly English Civil War weapons.
>> It turned out there was an "obvious" FTL method that mankind had
>> somehow missed that was usually found by civilizations when at the
>> 17th century level of technology - since we didn't find it, our
>> military technologies kept developing and we were thus MUCH more
>> dangerous when we accidentally captured such a ship.

>
>This is "The Road Not Taken", by Harry Turtledove.
>
>It's a good read, and probably short enough to finish without leaving the
>bookstore. :)