There are two potential causes of revolution in the United States: slavery and the high protective tariff.
Frédéric Bastiat passed away before the American Civil War burst out. Today’s quote reflects how sharp his understanding of the world was, at least concerning the first half of his proposition. Protectionism has evolved tremendously since but has not been crushed, unfortunately.
Here, the United States are the object of his thoughts because this is where he finds the greatest space of liberty at the time. However, he acknowledges its imperfection and finds the source thereof within the inappropriate intervention of the government. Indeed, slavery represented the utmost restriction of liberty that a government could organise (denying all rights to a certain class of individuals) while protectionism and regulatory restrictions constituted and still constitute nowadays the illegitimate intervention of the State, discriminating some individuals for the benefit of other individuals.
One can see once more the mistake of those who think that slavery was an attribute of capitalism. Capitalism ended slavery and the liberals of the 19th century had a clear understanding of this – their thirst for liberty could not be satisfied with such an attack against freedom.