Resource scarcity and overpopulation

Resource scarcity and overpopulation tend to solve themselves via population collapse due to epidemics, internal conflicts which lead to a total breakdown, or wars which cause a large number of deaths and reduce birthrates. 

In recent years we have seen this mechanism work in Rwanda, where genocide and war reduced population pressure, and Haiti, which seems to be a collapsed society sustained by charity and migration. 

While theoretically it's possible to overcome overpopulation and resource depletion, many nations are controlled by inept governments following the wrong recipes (see Venezuela for an extreme case of a marxist and gangster hybrid mentored by the Castro dictatorship wrecking a rich nation and causing 10-15% of the population to flee while killing hundreds of thousands from murder, hunger and disease). 

The Castro dictatorship ruined Cuba, and 

then its ideology jumped to Venezuela

The problem, as I see it, is that misgovernance and corruption are fairly common, and therefore in the next few decades we are likely to see more collapses, famines, wars, and epidemics caused by poor governance. To make matters even worse, richer nations such as many of the European Union members and the USA seem inclined to commit suicide by reducing their birthrates and simultaneously allowing themselves to be invaded by people fleeing misgoverned societies...which can be extrapolated to the eventual replacement of well governed societies by conflict ridden and badly governed constructs brought about by possibly well meaning but misguided political parties. This means that partial collapse of civilization may have already begun, and the world will eventually be ruled by smaller populations of survivor types such as Russians and Chinese.