In the second book, Frodo starts to lose his faith in his ability to complete his task and in the third book; his attempt to reform Smeagol fails as Smeagol leads him into the Spider's den. It is up to Sam to remind Frodo the answer to Frodo's question, "What are we holding onto?" by responding, "That there is some good in this world and that's worth fight for."

This book also details betrayals as well and not just betrayal of good and evil but evil against evil. In the second book, the wizard Saruman wishes the ring for his design and there is even a thought that he wants to replace Sauron as the new evil leader of Middle Earth. This happened in real history as Germany betrayed Soviet Union in 1941 by invasion and in 1939 when the Soviet Union made their peace with Germany and abandoning the West as well splitting up Poland with the Nazis. History is full of evil men betraying each other to gain advantages.

Tolkien theme of power corrupting is seen through first the descent of Gollum into madness as the ring destroys the very humanity that once was his. Another example is Denethor, the steward of Gondor. The ring corrupted Denethor's first son Boromir and Denethor's sends his second son Faramir on a suicidal mission. The final act of madness occurs when he attempts to burn his wounded son alive along with himself. Madness affects Denethor when he even refuses to step aside for Aragorn, which is his primary responsibility to begin with. Even Frodo is corrupted as he stands before the fiery pit, incapable of dropping the ring into it. Frodo's own final corruption is complete but he is saved by the intervention of Gollum, whose last act of selfness saves the race of men as he holds the ring for one last time before slipping into the fiery pit while holding on to the ring. He has his precious but with it, his final damnation. As Frodo tells Gandalf, even Gollum has a role to play in men's salvation.

Tolkien had his own experience with War as he served in the trenches during World War I. When the battle of Helm's Deep begins, we are witnessing a great race fighting for its very survival against the minion of Saruman's army of Orc-slaves. Tolkien past experiences with war allowed him to describe the battle of Helm's Deep with such accuracy. You believe that you are there. While Tolkien denied that his book was an allegory for World War II, there is no doubt that Tolkien drew from history and we still can. For the past seventy years, we have been engaged in a war of ideology in which freedom has been and still is threaten nor is everyone in agreement that there is a war happening.
The lesson from the Lord of the Ring is that evil exist and had existed in the past. In the 20th century, there was the evil of Hitler and Stalin. Today, there is Islamic fascism that is threatening security and liberty of the world. Evil exist. In the end of the Lord of the Ring, Frodo witness the cost of the war as his little town has changed and been effected by the war. Cost of the struggle reached all.