One thing is different about the USA: it's still a growing country.

Western Europe, Japan, and even China all have a demographically aging society.  The US does not. 

Everyone likes to say that the US population is growing because of the Hispanics.  That's not true.  If you look deeper, there are still many well-educated, highly motivated, professionally skilled immigrants coming into the US.  This new blood makes the US different from other countries.  And this new blood will keep driving the innovations in all sectors of the US economy.  

On the other hand, the lower-skilled immigrants also serve to keep the US labor cost at a reasonable level.

The US grad schools are full of foreign students.  As long as more of these students are staying in the US than returning to home countries after graduations, the US will still be a growing country.