There has been US government infringement on free markets since the day after the Constitution was ratified. Look up the Whiskey Rebellion for more information.
Before that, tariffs on sales of goods across state borders and with European businesses were part of the justification for amending or rewriting the Articles of Confederation, resulting in the Constitutional Convention.
The US government punished businesses in Southern states in the years prior to the Civil War, through selective tariffs and blockades.
Lincoln instituted wage and price controls and rationing during the Civil War.
The Federal government continued to selectively suppress Southern commerce during Reconstruction, to benefit Northern businesses.
The presidency of Woodrow Wilson was marked by oppressive wage and price controls, minimum and maximum production quotas for private industry, confiscatory tariffs, and outright prohibitions on doing business with companies from certain nations in the name of 'neutrality'.
Governors ordered banks to close in 3 or 4 states in 1933.
FDR ordered the closing of every bank in the US for 8 days (effectively nationalizing the industry when they reopened), stole every ounce of privately owned gold that he could get his hands on 'under color of law', nationalized production industries, selectively subsidized agriculture, and instituted rationing of consumer goods.
And let us not forget Prohibition, or the Cuban embargo.
So when, exactly, did the United States have a free market?