What is Neocolonialism?
"Neocolonialism" differs from "postcolonialism" in that it is not about addressing the wrongs of the past, as the latter movement is, but repeats many of the wrongs from the past, particularly economic exploitation and the subordination of people who live in dominated territories.
The United States' relationship with Puerto Rico is a good contemporary example of how Neocolonialism works. The US extends its influence over the island both economically and politically because Puerto Rico is a commonwealth.
Puerto Ricans have the benefit of American citizenship and can come and go into the mainland US as they please, but, like many people from colonies, they are still regarded as foreign. This is an important aspect of Neocolonialism—citizens under a neocolonial regime are still regarded as "Other," particularly when they are not white.
The United States gets tax revenue from Puerto Rico, but Puerto Ricans do not get the same representation in the federal government as states. This fact became quite clear in the aftermath of Hurricane Maria, which devastated the island. While the Trump administration rushed to support those who suffered from Hurricane Harvey in Texas and the Gulf states, there was far less relief available to Puerto Rican citizens, many of whom had gone for weeks without food and clean water and months without electricity.
Neo-colonialism can be defined as colonialism through other means. Under neocolonialism, the more powerful country will not actually have its soldiers occupying a country or running its government, but will rather have so many economic and social ties that the smaller, weaker country is basically under the control of the more powerful country. While France no longer maintains colonies in Africa, some nations such as Chad, are so deeply entwined with France that it can be said to be a neocolonial relationship.
Webster's defines Neocolonialism as "the economic and political policies by which a great power indirectly maintains or extends its influence over other areas or people." That is, it is not necessary to establish colonies or settlements within another country in order to establish power over it. For instance, you might say that the relationship between the United States and Afghanistan is an example of neocolonialism.