Which of these inferences about the speaker is best supported by the passage below (paragraph 1)?

He was finally free, but there was no joy in his heart. He thought there never would be again. Liberated a day earlier by American soldiers, he remembers their rage at what they saw. And even if he lives to be a very old man, he will always be grateful to them for that rage, and also for their compassion. Though he did not understand their language, their eyes told him what he needed to know—that they, too, would remember, and bear witness.