American dynamism

From City Journal:

America’s economic might is rooted in an entrepreneurial culture and a passion for innovation and risk-taking, traits nourished by the nation’s commitment to the rule of law, property rights, and a predictable set of tax and regulatory policies. Policymakers have lost sight of these fundamental principles in recent years. The next era of American prosperity will be hastened when they return to them.

This may be a stupid question, but why is economic "growth" the thing people are always going on about?  Isn't the notion that an economy always should be growing and expanding (in order to... what?  In order to meet liabilities, like the interest on the US debt?) sort of unhealthy?  The definition of a bubble almost?  Is it possible to have an economy that maximizes value, GDP remains constant for a long period of time, and everybody lives quite nicely, using goods and services that are all produced within the economy, or at the very least that an economy is self sustaining and not dependent on imports?  Is it possible to do this on a macro scale?  Why growth, though, I wonder.  The way things stand now, "poor" people have it far better in their everyday life than did the upper echelon in the 1950s, with tons more gadgets and comforts.  What are we going for here?  The new America feels like a huge colossal bubble.  It was the greatest country on earth for specific cultural based reasons that fueled its dynamism.  The American ideals of freedom, rule of law, work ethic, etc., which drove its success are gone, as shown by our "Paper Tiger" responses to 9/11 and by the rise of Obama, particularly his reelection in 2012 once the cards were on the table (and, yes, while it's true that Obama would not have won had not our rulers have tinkered with our demographics over the last half century, it boils down to the same thing, because America's foundational and historical ideals were culturally rooted).  America is now just a geographic place on the map, with a government like any other, yet we have all these things, which were essentially dropped into our lap.  We cannot make them, haven't earned them, and won't fight for them.  A real reordering is called for in the lives of individuals, a reexamination of first principles.