The key sentence is: "<span>We are apt to shut our eyes against a painful truth, and listen to the song of that siren till she transforms us into beasts." This means that if the leaders continue to act like nothing is wrong, they will gradually become desensitized to their wrongdoings until they think their actions are right. no matter what.
The line "</span><span>I consider it as nothing less than a question of freedom or slavery" may appear to be similar, but that is not talking about the issue itself yet, but just about the magnitude of it, or how serious the issue is that it needs an open discussion.</span>
Sweep is the action word because sweep is the only verb found in the sentence
On and under are grammatically correct the other 2 are questionable
Explanation: Here's and example
I parked the car HERE
I parked the car RIGHT HERE
I parked the car RIGHT HERE UNDER THE BRIDGE
The wors in all caps are examples of adverb phrases
In Musèe des Beaux Arts by W.H. Auden the people on the ship do nothing after seeing Icarus fall into the sea and the ship continues on its way. Why was that? Because according to the author, when a tragedy happens, human beings are not affected by it if their interests are protected and they have an horizon to pursue.