Would you consider all the ideas covered/discussed in Joseph Conrad's Heart of Darkness historically specific, or are they still relevant in today's world?

One need only look at the themes in Conrad's Heart of Darkness to find that the book is as relevant today as it was when Conrad put pen to paper.

This short novel's themes include:

• Alienation and loneliness
• Deception
• Order and disorder
• Sanity and insanity
• Duty and responsibility
• Doubt and ambiguity
• Race and racism
• Violence and cruelty
• Moral corruption

We can identify all of these issues as characteristic of human behavior as long has man has walked the earth. When one group exerts its power and control over a weaker group, all of these elements are present. Look to the Middle East and Africa (as in the novel), in recent years in places like Iraq, Afghanistan, Libya, Darfur, the Sudan, etc., to find insanity, deception, disorder, violence and cruelty, moral corruption, etc.

As an example of order and disorder:

Sudan has been at war with itself for almost its entire post-colonial history, starting in 1956.

...reconcile groups with long-running grievances...[and has failed] to bring many of the militias that deposed Gaddafi fully under its control.

 

They were dying slowly—it was very clear. They were not enemies, they were not criminals, they were nothing earthly now—nothing but black shadows of disease and starvation...

...it seemed to me as if I...was buried in a vast grave full of unspeakable secrets. I felt an intolerable weight...the unseen presence of victorious corruption, the darkness of an impenetrable night.

The horror! The horror!