Give me Growth!

Every politician is promising growth; Trump says 4% a year would be good, because the current 2% is a “disaster”.

The Europeans want more growth too, so are the Chinese, the Senegalese and the 200 others countries in business around the planet.

Are we to compete in a “zero-sum game” in which we steal business from each other, or do we believe that the pie, i.e. the population will keep on growing to sustain the unsustainable?

Where is that magical growth going to come from? Can an “economist” explain this to me?