Douglas Wolk talks about this passage in his book Reading Comics
He writes on Page 292-93 in his book- He asks the prisoner before him the same question Pilate asked Christ: "What is truth?"
Sim provides plenty of answers, which of course aren't very satisfying- a bitter running joke is that every time any of his characters explain the way things are, either they're lying to serve their own interests or they're simply deluded, even if what they're saying makes perfect sense at the time. Some characters poach their subjective truths word for word from real-word writers; one volume ends with a passage from John F. Kennedy's inaugural address being written on a cell wall by an imprisoned, idiotic "Anarcho-Romantic" aesthete who believes that what he thinks is Cerebus's philosophy (it's not) is the great hope of the common people - or as most of the characters in power call them, "the peasants and livestock." The scene is set up as a swelling-strings moment, and you can take what he's writing ("we shall pay any price, bear any burden meet any hardship, support any friend, oppose any foe, in order to assure the survival and the success of liberty") at face value if you like- it just means you're being willfully blind to its context.