Question

how did these planks of the republican platform promote the industrial and commercial growth of the country

Answer 1

Republican economic policies are a focal point on what is good for businesses and investors. They are of the view that flourishing companies will boost economic growth for everyone.  

Explanation:

The Republican Party's traditionalist policies engage in support for free-market capitalism, free enterprise, creating a good business environment that intern boosts the growth of the country. They have a good national defense policy which will focus on primary security of US citizen.  

They want to protect the exploitation of labor so they advocated labor laws pertaining to present working conditions. They are concerned with various social issues namely abortion, the Equal Rights Amendment, same-sex marriage, and traditional values, usually with a Christian foundation.