Social democracy is not a form or variety of socialism. From Wikipedia (emphasis mine): "Social democracy is a political, social, and economic ideology that su

Social democracy is not a form or variety of socialism. From Wikipedia (emphasis mine): "Social democracy is a political, social, and economic ideology that supports economic and social interventions to promote social justice within the framework of a liberal democratic polity and capitalist economy." "Socialism is a range of economic and social systems characterised by social ownership and workers' self-management of the means of production" And the U.S. government generally does not own the means of production (there may be a few small exceptions). In all of the examples you cite (aircraft, roads, and highways), the government is buying something that is produced by a non-governmental corporation. That is not the same as owning the means of production, which would entails something more like the government owning the heavy equipment used to make roads and highways and employing the workers who operate those machines, or the government owning and operating airplane factories.