The making of a Super Power

What makes a country a superpower?  A large population is right up there in importance.  A country of 100 million can overwhelm a country of 1 million in any field of endeavor, athletics, warfare, innovation, popular culture, manufacturing, you name it.  We have enjoyed superpower status since the beginning of the 20th century. 
  Part of  obtaining and holding onto a large population is political skill, skill to prevent the large country from breaking down into smaller parts.  Like what happened to the USSR in 1989, Czechoslovakia, what almost happened to the US in 1860.  And what is simmering under the surface in Canada and Britain and other places. 
  For the large population to be an element of strength, it has to be loyal, willing to make serious sacrifice to their country. Unhappy Muslim "youths" from the banlieus around Paris, rioting in the streets and setting fire to 1000 cars in one night, are not loyal, in fact they are traitors to France.  Japanese Americans enlisting during WWII and creating a heroic combat record, despite their families treatment in American concentration camps, are loyal. 
   Traditionally, native born and raised citizens are loyal.  Loyalties of immigrants are not so certain.  Here the US is fortunate,  immigrants come to the US because they like our liberties, our economic opportunities, our civil order,  and the vast amount of good America has done around the world for all of our history.  Immigrants to the US become astoundingly loyal to America, and pass this down to their children.  And immigration has grown our population from great power size to super power size.  Without the great 19th century immigration the US would be more like Canada, a worthy country, but hardly a super power. 
    The other method of keeping up the population is is natural increase.  In principal if each woman bore two children in her lifetime, she would have replaced herself and her husband and kept the population steady.  In practice, to make allowances for early death from disease, accident, crime, and warfare, the number is 2.1 children.  If  each woman were to bear three children, then the population grows rapidly, like 150% in a generation.   Right now,  US women are bearing just exactly 2.1 children, just enough to keep the population steady.  Places like the EU, Russia, and Japan are much worse, rates as low as 1.1 children have been reported from Russia. 
    So, we need immigrants to grow our population, especially with international competitors like China and India out there.  We especially need young, married immigrants, who will take jobs and grow the economy.