Final answer:
The fall of communism cannot be explained by Marx underestimating difficulties in creating a wealthy, classless society as several other factors led to its demise.
Step-by-step explanation:
The demise of communism as an economic and political system can be attributed to several factors but cannot be explained by the fact that 'Marx had underestimated the difficulties of creating a society that was both wealthy and classless'. Indeed, one of the central contradictions of communism was the requirement for at least a temporary centralization of government power. This centralization led to the disinclination of authoritarian governments in Eastern Europe to relinquish their powers, contrary to the communal and classless society that Marx envisioned. However, in the late 1980s, rather than facing bloody counterrevolutions and civil wars, most Communist leaders prudently allowed for free elections paving the way for democratic transitions.
Notably, the mass uprisings that led to the toppling of these governments coincided somewhat with Marx's predictions of proletarians rising against autocratic regimes, but the irony was acute; these democratic surges were directed against regimes that claimed to embody the communist ideal. Furthermore, grassroots efforts, global leaders like Pope John Paul II, and U.S. allies such as Britain played significant roles in the transitions, making it an international effort rather than solely a result of internal failures.