There is an economic role for government to play in a market economy whenever the benefits of a government policy outweigh its costs. Governments often provide for national defense, address environmental concerns, define and protect property rights, and attempt to make markets more competitive.
(Source 2)
Governments can create subsidies, taxing the public and giving the money to an industry, or tariffs, adding taxes to foreign products to lift prices and make domestic products more appealing. Higher taxes, fees, and greater regulations can stymie businesses or entire industries.