That's not how that works.
Capitalism does not require universal free trade. That's not viable under any system.
Edit:
capitalism/kăp′ĭ-tl-ĭz″əm/
noun
An economic system in which the means of production and distribution are privately or corporately owned and development occurs through the accumulation and reinvestment of profits gained in a free market.
An economic system based on predominantly private (individual or corporate) investment in and ownership of the means of production, distribution, and exchange of goods and wealth; contrasted with socialism or especially communism, in which the state has the predominant role in the economy. Similar: capitalist economy
A socio-economic system based on private property rights, including the private ownership of resources or capital, with economic decisions made largely through the operation of a market unregulated by the state.