I remember this fondly from my childhood, no doubt watching it at my grandmother's apartment when it came on Disney. It would be years later before I read Rudyard Kipling's story version of this.
When teaching Brit Lit I had a student write an essay in which she interpreted the Kipling tale as a fable for colonialism (as the British Empire took over most of the world . . . in that case the British Empire is represented by the British family while the indigenous people are depicted as the villainous snakes. I'm sure Rikki Tikki Tavi, the real hero of the tale, is representative of the natives who realize the "civilization" that the colonials are bringing and work to help them rid the native land of its "traditional" ways . . . I know . . . only an English major would delve into a children's work so much).
When I saw this on the Smithsonian website, a real mongoose taking down a real deadly snake, I was reminded of the Kipling tale.
You have to respect the mongoose's moxie.
When I watch it eventually defeat the snake (sorry to ruin it for you), as the mongoose manages to snap the snake's next, paralyzing it and seeing it lie there unable to move as it is about to be eaten alive, I can't help but think of what my father would always say about nature . . . it's cruel.
But that's nature. And that makes me glad I'm human. And that reminds me of one of our main goals as humans (or at least what I think should be one of our main goals): to make the world far less cruel.