I love this poem because Pope pokes fun at uppercrust London society via epic form (he uses heroic couplets, which makes the poem even more satirical because there isn't a hero to be found).
First, Pope tries to deflate classic heroic discourse using a technique called the heroi-comical (now called the mock-heroic). He was the first to do this, so it's especially funny that the poem is based on a true story of hair purloining and a real rift between two gentrified families. His main focus was to show how society, through an uber-focus on colonialism, was morphing into trivialities.
Pope spends a fair amount of time teasing the symbols of social status. Nobody actually does anything other than put makeup on and drink coffee--those are the battles. He spends some time discussing Belinda's daily routine, which is equally unimportant. He illustrates the frivolity and stupidity of the colonial enterprise. What are the tortoise shell and ivory combs being used for? Makeup and hair combs for Belinda! Even military valor and imperialism are sullied. Pope teases the classical gods (there are no gods and goddesses, merely gnomes) and mocks aristocratic religion.
Equally, Pope's plot dramatizes the race between male/female sexes as a 'war' in which men are trying to possess women (in the salon as a result of a cut piece of hair). I pulled the quote below from an excellent e-notes study guide:
"A common thread in much twentieth-century criticism of The Rape of the Lock has acknowledged the way in which a deep appreciation for English high society meshes with Pope's critique of its weaknesses"
In the end, the poem forces readers to look at the vacuous lives people were leading. The poem could have been an abysmal failure but ended up (A) rejoining the two slighted families and (B) becoming one of Pope's most brilliant masterpieces. By his focus on maintaining the epic form, he delivers a silly--yet compelling--reminder of how societal values were decomposing.