...why can't a President have the right answer?
Occupation of government office proves that the occupier desires to compel others to comply with the occupier's preferences.
A president may, possibly, have a right answer for something, but his occupation of office requires that everything
he does be held highly suspect.
As for the ability of a president, or anyone
, to fix
an economy: it's not possible, except in the sense of fixing
a fight. The Fed and its toadies on the Potomac have fixed things good.
We're seeing now the result of many decades of pecuniary sleight of hand and societal manipulation.