Is Aragorn Racist?

Interestingly, Tolkien seems to have regretted that he made the orchs appear that way.

J. R. R. Tolkien's Middle-earth stories have evil creatures mutated from natural ones by Dark Lord Morgoth: Orcs, Trolls, Dragons, Werewolves, Wargs, etc. However, as a devout Catholic who believed in spiritual salvation, the idea of a race of inherently or irredeemably evil creatures was one of Tolkien's major sticking points with his own work. He spent much of the latter part of his life as a writer trying to justify it. He never did come up with an explanation that satisfied him.
Orcs: In The Silmarillion, the Elves theorize that Orcs were Elves tortured and corrupted by Morgoth, and in The Lord of the Rings Treebeard voices a similar theory about Trolls being bred as a mockery of Ents. Both of these are beliefs of characters, which are never directly confirmed by the author. Another idea was that Orcs are generally just Human tribes and are "evil" precisely because of Sauron and Morgoth's magic. After the One Ring is destroyed, they become feral and scatter in all directions.

These later explanations of Orcs can be seen as an exploration of institutionalized abuse and slavery. While they may be a "species" genetically distinct from their Elf and/or Human ancestors, their evil cultures resulted from millennia of slavery, Religion of Evil, and deliberate corruption. They are less inherently evil than a race that's been warped by external forces into cannon fodder. Tolkien even wrote "deep in their dark hearts the Orcs loathed the Master (Morgoth) whom they served in fear, the maker only of their misery."

Perhaps the most tragic and frightening thing about Orcs and Trolls is that we can never know what they would be like if Morgoth and Sauron hadn't ruined them, or if any of them were able to grow up in a less cruel culture. They're never given the opportunity to be anything but evil. They're raised in cultures that encourage hoarding and greed and the differences between them incite the violent tendencies bred into them by the Dark Lords. In an Orc society, cooperation would reduce your own chance of survival in a dangerous situation (i.e. leave your partner to the wolves and escape on your own). Sauron's propaganda also convinced them that their enemies, particularly Elves, were even crueler than Orcs, to discourage them from ever surrendering in battle. It's worth noting that the Forces of Light are essentially waging an extermination war against the Orcs and likely wouldn't know what to do with any that actually surrendered peacefully.

In one letter, Tolkien points out that some Orcs display courage and tribal loyalty if nothing else, and that they wouldn't have been able to function as well if they were completely evil. And he was generally quite good at giving individual Orcs distinct personalities. (This is touched on in the animated version of The Return of the King, where some orcs sing that they don't want to go to war but their officers and Sauron tell them to.)