Interventionism is not an economic system, that is, it is not a method which enables people to achieve their aims. It is merely a system of procedures which disturb and eventually destroy the market economy. It hampers production and impairs satisfaction of needs. It does not make people richer; it makes people poorer.
Concededly, the interventionist measures may give certain individuals or certain groups of individuals advantages at the expense of others. Minorities may obtain privileges which enrich them at the expense of their fellow citizens. But the majority, or the whole nation, stands only to lose by interventionism.
From Chapter IV, "The Economic, Social, and Political Consequences of Interventionism" in his book Interventionism: An Economic Analysis. Written in 1940, the work is an excellent investigation into the nature and consequences of government intervention in the economy.