What feelings does George Orwell portray about imperialism in "Shooting an Elephant"?

Orwell's "Shooting an Elephant" is in many ways an indictment of imperialism. Based on his own experiences as an imperial policeman in the British colony of Burma (modern Myanmar) the short story illustrates the ways in which imperialism is fundamentally corrupt. At the beginning of the story we see that the narrator feels despised by the Burmese people. They laugh at him when he is tripped in a football match, and he describes the "sneering yellow faces of young men that met me everywhere" in Moulmein, the town where he was posted. As this line and others demonstrate, the young police officer didn't much like the Burmese people either. One of the "natural by-products of imperialism," the narrator tells us, is this feeling:

With one part of my mind I thought of the British Raj as an unbreakable tyranny, as something clamped down, in saecula saeculorum, upon the will of prostrate peoples; with another part I thought that the greatest joy in the world would be to drive a bayonet into a Buddhist priest's guts. 

But it is the story's central event that best demonstrates how Orwell feels about imperialism. When the elephant rampages through the bazaar, it unwittingly tramples a man, killing him. The crowd is eager that he, as a police officer, shoot the elephant, which he does not wish to do, given that it has by that point calmed down and is, after all, a "huge and costly piece of machinery" in Burma. But the crowd expected him to, and he realized at that moment that his role as an agent of empire required him to act in a way that was contrary to his personal sense of right and wrong. They expected him, in short, to act violently, because that was in the final analysis the basis of British rule. 

So when he pulls the trigger, and kills the elephant, he is playing a role prescribed for him by his situation. The process of killing the elephant itself is long and excruciating, worsening his regret. But what really bothers the narrator is that he killed the beast out of a desire not to be laughed at by the crowd, an overriding preoccupation of the people charged with administering the British Empire at the local and personal level. As the narrator puts it, this incident gave him a "better glimpse than I had had before of the real nature of imperialism – the real motives for which despotic governments act."