Today’s "year in which the contemporary world began" is 1910. In that year, the German Social Democratic politician Rudolf Hilferding published Finance Capital in Vienna. The title suggests its purview: it was a conscious extension of Marx’s theory of capitalism to a new era. This was an era in which banking and finance capital had become autonomous from, and dominant over, industrial capital; an era in which the "joint-stock" limited liability corporation had become the dominant ownership form, and in which this whole structure had become fused to the vast enterprise of global imperialism.
The structure looked unassailable. In fact, Hilferding argued, these were all developments which made socialism possible. Taking Marx’s point that the next social system develops within the contradictions of the previous one -- as merchant capital became industrial capital within the dying structures of feudalism -- Hilferding argued that via financialisation and monopolisation, capitalism was socialising itself. What Marx had called "the anarchy of production" (small proprietors competing, railway companies laying separate tracks side-by-side, etc) was being transformed into a system of planned production. The content of it was currently capitalist; the form could be taken over and rendered socialist.