It is an adjective in this sentence. devasting [adj.] ends [noun] It could be a verb in sentence like: The low price of oil is devastating the economy. 'to' tell us that it is moving towards this outcome. We usually need a preposition with 'use (something) to/for/with/as ...'. I used the needle to make a hole. [method] I use the computer for work. [purpose] I use the computer with the large screen. [possession] I used the newspaper as an umbrella. [function]

It's a present participle form here, so it can take the place of an adjective. The last part of the sentence is related to the phrase "the means to an end", ie. the process by which you get a certain result. We also ask "to what end?" when we want to know what kind of result someone expects from their actions. So, "to" is not part of a verb but it tells us of a transit towards something.